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Garden Tips Archive


February 2023

Right Plant Right Place

Winter months give us time to dream and research what we will plant in the coming seasons. However, research is the important word for a successful garden.

Start with a sketch of your space then answer some of the following questions:

  • How much sun is there during the growing season?
  • Have you considered shade from deciduous trees, nearby buildings and fences?
  • From what direction is the prevailing wind?
  • Are there protected areas created by structures?
  • Is there standing water during wet months?
  • Will nearby plants crowd your new addition or will your addition soon outgrow its space?
  • Is the soil amenable to the selected plants?
  • Will the house overhang prevent rain from reaching plants there?

This information guides your choice of plants. Read the plant tag, as well as written and online resources, to get the scoop on what your prospective addition needs to grow well. And be sure to research the specific variety you are considering, as cultural needs can vary within species.

One focus should be the soil. Soil tests will reveal the pH of your chosen site and can be critical for certain plants. Also important is soil moisture. Some plants need quick draining soil or they get root rot or simply don’t thrive. If you are planting under a large, well established tree, you will be fighting a lot of roots that will also suck moisture out of the soil around your new plant.

What is the light requirement for your plant?  While full sun is good for many plants, others need filtered or full shade.

Look for microclimates on your property such as sun or shade pockets or areas shielded from wind. Then pick the perfect plant to reside there.

February Tips:
  • Wake up any stored fuchsias and geraniums by pinching back spindly stems, water with warm water, and move closer to indirect light.
  • Pull or hoe annual weeds.
  • Cut your deciduous ornamental grasses back by the end of the month.
Untitled Design 1
February Tips:
  • Wake up any stored fuchsias and geraniums by pinching back spindly stems, water with warm water, and move closer to indirect light.
  • Pull or hoe annual weeds.
  • Cut your deciduous ornamental grasses back by the end of the month.

January 2023

Rejuvenating Holiday Plants

Poinsettias can be grown as attractive green plants after the holidays, but many steps are needed for your plant to bloom again next holiday season.  You will need to keep it well-watered and in a bright window – or outside during warmer weather – until the Fall Solstice. Then it will need a regimen of uninterrupted darkness with periods of bright light for two months.  This will prevent the poinsettia from producing chlorophyll, which makes plant parts green, and allow its bracts to change to red, pink or white, depending on the variety. For more details on how to proceed, click here.

Amaryllis (Hippeastrum) can also be rejuvenated post bloom by fertilizing, watering and  placement in a sunny window, followed by a resting period.  Learn more here.

Poinsettias
January Tips:
  • As bare root roses will begin to arrive in nurseries in January and February, now is the time to assess good planting sites in your garden for your new purchases.  Make sure the site has good drainage as roses don’t like damp feet in winter months.  It should also have at least 6-8 hours of sun per day and be large enough to enable adequate air circulation between plants, to help prevent disease.
  • The drooping leaves on your rhododendrons during our very cold days is simply the plants’ defense against adverse conditions. Leave any browned foliage on them and your other shrubs if its firmly attached.  Stripping it off might incentivize them to begin new growth.
  • When spring bulb foliage emerges from the ground, it will appreciate some 5-10-5 fertilizer.

January 2023

Rejuvenating Holiday Plants

Poinsettias can be grown as attractive green plants after the holidays, but many steps are needed for your plant to bloom again next holiday season.  You will need to keep it well-watered and in a bright window – or outside during warmer weather – until the Fall Solstice. Then it will need a regimen of uninterrupted darkness with periods of bright light for two months.  This will prevent the poinsettia from producing chlorophyll, which makes plant parts green, and allow its bracts to change to red, pink or white, depending on the variety. For more details on how to proceed, click here.

Amaryllis (Hippeastrum) can also be rejuvenated post bloom by fertilizing, watering and  placement in a sunny window, followed by a resting period.  Learn more here.

Poinsettias
January Tips:
  • As bare root roses will begin to arrive in nurseries in January and February, now is the time to assess good planting sites in your garden for your new purchases.  Make sure the site has good drainage as roses don’t like damp feet in winter months.  It should also have at least 6-8 hours of sun per day and be large enough to enable adequate air circulation between plants, to help prevent disease.
  • The drooping leaves on your rhododendrons during our very cold days is simply the plants’ defense against adverse conditions. Leave any browned foliage on them and your other shrubs if its firmly attached.  Stripping it off might incentivize them to begin new growth.
  • When spring bulb foliage emerges from the ground, it will appreciate some 5-10-5 fertilizer.

December 2022

Problem Solving

Part of being a gardener is problem solving – a common focus being what agent or agents are impacting your plants. Are they being eaten by pests, do they have a fungus,  are they affected by drought? Answers to these questions and others can be found by submitting them to our local Master Gardener Diagnostic Plant Clinic or at an Ask A Master Gardener table. But there are also many problem-solving tools available online from universities across the nation. These provide research-based information on how to recognize whether the symptoms you are observing are caused by the environment, disease agents, or pests, and how to mitigate them.

These tools can be reached by several methods. One way is to type a short phrase followed by .edu, or the initials of a state agricultural school like wsu (Washington), or other educational institutions in nearby states with similar climate zones, such as oregonstate (Oregon) or uidaho (Idaho). This will pull up articles and monographs focusing on your search topic. Other valuable information can be found at these links:

WSU Hortsense: Fact sheets for managing many common landscape and garden plant problems

WSU Vegetable Problem Photo Gallery

WSU Gardening in Washington State: Free publications on all aspects of gardening

Closeup,image,of,a,woman,working,and,typing,on,laptop
December tips:
  • Intermittent freezing and thawing of the soil during winter months can heave perennial plants out of the soil, baring their roots. A layer of mulch, 2 to 3 inches deep, will help prevent this. You can even add your Christmas greens and tree branches.
  • Don’t keep your live Christmas tree indoors more than ten days and be sure to keep it moist.
  • If applying dormant spray to your fruit trees, don’t spray when the temperature is below 40o, when it has rained in the past 36 hours, or if rain is expected in the next 24 hours.

November 2022

Forcing Bulbs Indoors

Now that you have finished planting spring blooming bulbs in your yard, it’s time to concentrate on enjoying the beauty of bulbs forced indoors. Many bulbs require a cold treatment of several weeks first, so if you are hoping for a Christmas display this year you should focus on amaryllis or paperwhite narcissus that do not.

Both can make a stunning statement in your home, but the process to bloom is a bit different. Place bulbs in a container with just enough potting medium (soil, pebbles) to cover the roots and stabilize the bulb. Add water just to the bottom of the bulb to avoid bulb rot. Special glass containers that provide support for bulbs above a water reservoir can also be used. Amaryllis can be placed in bright light initially, while paperwhite narcissus should be kept in very low light until they sprout. Paperwhites also tend to grow tall and leggy, but Cornell University research has shown that using diluted alcohol as the watering medium keeps them shorter. Follow these links for more details on forcing various types of bulbs:

  • Pickling Your Paperwhites
  • Forcing Bulbs (Clemson Cooperative Ext.).
  • Forcing Bulbs (Univ. of Wisconsin Ext.)
Red,amaryllis,flower,in,pot,isolated
November Tips:
  • Don’t compost any apples with apple maggot, or especially pernicious weeds such as morning glory or horsetail, as they may not be killed by typical home composting temperatures.
  • Brown tips on your Western Red Cedar branches are caused by drought. Brown needles higher on the branch are due to natural seasonal shedding.
  • The algae, lichens, mosses and liverworts on tree branches that become more visible once leaves fall cause no harm to your trees.

October 2022

Putting Your Garden to Bed

As fall arrives, resist the urge to tidy up your garden by cutting everything to the ground and gathering up all of the leaves. Think instead of this time as a period of rest and renewal for your plants and the many creatures that benefit our world. Fall leaves and standing dead plant material support pollinators and other invertebrates by providing them with needed winter cover. The seed heads on your perennials offer garden interest as well as food for birds. Leaves provide valuable organic matter and build up healthy soil. They have also been shown to have the same weed and moisture retention properties as shredded wood mulch.

In your veggie garden, pull up your spent summer plants. However, leave the roots of any nitrogen-fixing legumes to nourish the soil. Cover asparagus and rhubarb beds with a mulch of manure or compost. Apply a mulch of leaves or straw or sow a green mulch cover crop to prevent erosion.

In your orchard, remove and dispose of windfall apples that might be harboring apple maggot or codling moth larvae. Rake and destroy diseased leaves and spray apple and stone fruit trees at leaf fall to prevent various fungal and bacterial diseases. Prune out dead fruiting canes of raspberries.

A,beautiful,pine,siskin,,one,of,hundreds,in,the,flock,
October tips:
  • When peonies die back, cut them to the ground and clean up the debris to keep diseases at bay. Divide and replant, if needed.
  • Control fall-germinating weeds while they are small.
  • Plant garlic and shallots

September 2022

Planting Trees and Shrubs

Trees and shrubs are important anchors in our home landscape, so for their long-term success, spend some time and energy to give them a good start. Don’t rush to get them into the ground while we are still in the midst of our hot and dry season. Wait until the fall rains begin and the weather has cooled.

Also, don’t jump the gun by pre-digging the planting hole. You don’t really know the size of the plant’s root ball until it has been taken from its pot or burlap, dirt removed, and roots examined and trimmed, if needed. The root ball should sit solidly on firm soil at the bottom of the hole. If the hole is dug overly deep and must be partially filled in, the plant will settle and end up being planted too deep.

Instead, gather what you need for planting day —adequate mulch to prevent moisture loss and staking materials if your tree is in a windy location. No soil amendments are needed as trees do better growing directly into the native soil at the site.

For detailed directions and photos about tree planting, click here.

Planting Tree 1
September tips:
  • If you buy bulbs this month, wait until late October, early November to plant – except for bulb lilies, which can be planted now. Store your bulbs in paper – not plastic bags – in a cool, dark place, but not your refrigerator.
  • Wait to pick your ornamental gourds until their stems turn brown and vines begin dying; otherwise, they will not last long.
  • Lawn seeding in early fall avoids competition with spring weeds and takes advantage of fall rains.

August 2022

Planting your Fall Garden continued

As discussed in the July column, our relatively mild winters allow us to extend our veggie growing season.  Plant the veggies listed below beginning now to get them established before our reduced sunlight and cold snaps slow their growth. For more information click here.

Mid August

  • Bok Choy (Chinese mustard) – seed
  • Lettuce (Leaf) – seed
  • Turnips – seed; for greens only seed through September
  • Spinach – seed for fall crop; seed in September for early spring crop

September

  • Corn salad (mache) – seed early September for fall use; seed late October to winter over for early spring use
  • Mustard Greens – seed through September for fall greens
  • Radishes (early varieties) – seed throughout growing season until mid-September

Late October, early November

  • Beans (Fava or Broad) – seed for June harvest
  • Garlic – plant cloves for early summer harvest
  • Onion – plant sets anytime during fall and winter if soil is well drained and workable
  • Peas – direct seed for an early June crop
Leafygreens 1
August Tips
  • Obtain cover crop seed for your fallow beds now and for others later this fall. Click here for more detailed cover crop information.
  • Evaluate your ornamental and veggie gardens to inform your plans for next year.
  • Wait until fall to transplant ornamentals and shrubs when the weather has cooled and plants are less stressed.

July 2022

Fall Gardening Begins Now

Relatively mild winters in Western Washington allow gardeners to extend their veggie growing season. However, as plants don’t grow much between November and February, due to reduced sunlight and cold snaps, winter vegetables need to get established in late summer and early fall. You also need to ensure that your garden beds are well drained to deal with our typical heavy rains. The vegetables below should be planted in July. Next month we will cover later plantings.

Early to mid July

  • Brussels sprouts, Ballhead Cabbage, Cauliflower (seed by July 1; transplants by August 1 for a fall crop)
  • Carrots – seed for fall and winter harvest
  • Kohlrabi – seed for fall harvest
  • Onions (green or table) – seed for fall use
  • Parsley – seed in early July for fall and spring use
  • Peas (green or edible pods) – seed for fall harvest
  • Rutabaga – seed for fall and winter harvest
  • Swiss Chard –seed for fall crop; seed in late August to winter over.

Until late July

  • Bush beans – seed  
  • Beets – seed (for greens only, seed until September 1)
  • Broccoli, Savoy Cabbage – seed (transplants until mid-August for late Nov harvest)
  • Kale – seed (transplants until mid-August)
  • Lettuce (Head & Romaine) – seed, Radishes (oriental types, Black Spanish) – seed for harvest all winter.
Roots Gia Parsons King Co Mg
July Tips:
  • Check leafy vegetables for caterpillars. Remove as they appear. Use Bt-k, if necessary.
  • In late July, begin to monitor tomatoes for early and late blight. Prune for good air circulation, pick off affected leaves, and/or treat with approved fungicide.
  • During hot, dry weather, spider mites may appear on ornamental plants, vegetables and fruit plants. Watch for dusty-looking foliage, loss of color and tiny mites. Wash infested areas with water or spray with appropriate pesticides.

Click here to read an informative publication about winter vegetable gardening from Oregon State University.


June 2022

Heirloom Vegetables

When visiting a farmers’ market or perusing vegetable seed packs, you’re likely to run across the term ‘Heirloom’. Offering a taste of the past, heirlooms are considered by many to have superior attributes such as flavor and tenderness that have been selected for over time by generations of gardeners.

If you save the seed of the best-tasting, best-performing plants in your own garden each year, for a number of years, you can gradually create your own heirlooms. However, this is only possible with open-pollinated seed. Open-pollinated plant varieties that cross-pollinate with other plants of the same variety, will reproduce almost identically to their parent plants, or ‘true to type’. Seeds from hybrids will not produce plants identical to their parents due to the special way they are created.

Saving heirloom seed lessens the need to purchase new seed each year. It also helps maintain the genetic traits of old varieties of food crops for future use. When old varieties are not maintained, the gene pool grows smaller and smaller, which can lead to increased disease and pest problems.

Black Seaman
June Tips:
  • To prepare for efficient watering during our dry season, determine what type of soil you have. Heavy clay soils take in water slowly; sandy soils let water pass through quickly and loamy soils absorb and retain water.
  • To deter flies and butterflies from laying their eggs on your garden crops – particularly Brassicas – cover your plants with fine row cover which will serve as a barrier.
  • If you’ve started your flower or veggie garden in a space that used to be grass, the roots or tubers of plants like potatoes or dahlias might show holes caused by wireworms. Using chemicals in a veggie garden isn’t the best option.  Instead, these larvae of click beetles can be diverted from these crops by putting fresh potato peels in a 4″ deep hole nearby and disposing of them weekly.

May 2022

Veggie Container Gardening

If you have limited space, or don’t want to maintain a full sized vegetable garden, container gardening may be for you. While stock tanks and wine barrels are commonly used, wooden crates, dresser drawers, galvanized buckets or containers that haven’t held toxic substances can also be repurposed.  Make sure there is adequate drainage by adding bottom holes if lacking. Can’t bend over because of a bad back?  Consider adding legs to your planter.  Not enough sun or too much?  Wheels can enable you to move your containers. Use commercial potting soil as garden soil tends to compact in containers.  It will also avoid soil-borne plant diseases.

Consider the size and growth habit of mature plants when deciding what you can grow in your containers. (Read the spacing recommendations on seed packets.) Leafy greens don’t need much space but squash does.  Root vegetables need deeper containers.  Tomatoes and vining veggies need added supports.

Generally, the larger the container, the less watering is needed  but checking daily is important. Due to more frequent watering, more fertilizing is needed – but at diluted rates.  For more in depth information check out this article: Home Vegetable Gardening in Washington

Best Vegetables For Container Gardens
May Tips:
  • Be on the lookout for garden pests. Ensure that the symptoms you see are not environmental, then review all options for treatment rather than moving quickly to spraying chemicals.
  • When applying mulch to your beds, make sure your soil is well watered first.
  • By keeping your lawn mower setting high (1½ inch) and mowing frequently, the clippings can remain on the lawn to decompose and add nitrogen.
  • Even though pollinators would prefer you didn’t– remove the stalk and flower head from your rhubarb plant so the plant’s energy will be directed toward making and storing food for next year’s crop.

April 2022

Getting Seeds in the Ground

With the advent of spring, we’re all itching to get plants and seeds into the ground, but what are some useful guidelines for what and when?  Checking the back of your seed packet gives you guidance on whether you can plant pre or post your local frost date. For early cool season plants, it might even say“as soon as soil can be worked”. The last freeze/frost date falls between May 5 and 20 for Whatcom County. However, the elevation and exposure of your garden also need to be considered.

Even more important is the soil temperature – whether you are planting starts or seeds.  This is generally 50 or 60 degrees, depending on the plant. Warmth-loving plants like tomatoes, eggplant, basil, peppers, and melons are especially sensitive to cool temps. Don’t rush to plant these. If you do, provide protection such as cloches, walls of water, or row cover.

Why should you wait? Cold can stunt growth or damage and kill parts of a plant, even the entire plant. Even if the plant isn’t killed, it has to expend energy on repairing the damage which can affect yield at harvest time. And in our damp climate, seeds planted too early, may rot before germinating.

Plantingseeds Aprilphoto
April Tips:
  • While this is an optimum time to fertilize your lawn, limit runoff into your local waters by not fertilizing just before rain, and not over-irrigating.
  • Do a spring cleanup of hiding places for slugs, sowbugs and millipedes. Baits are available for slug control but less toxic options include copper tape barriers, beer traps, or a daily slug patrol.
  • Wait to place organic mulch on your beds until they have warmed up – usually by late April.
  • Fertilize your berries.

March 2022

Cutting Back Perennials

While deadheading perennials can encourage repeat blooms, the practice of cutting plants back late in the season to manage their size, remove unsightly material and keep them healthy can be tricky in regard to timing.

Popular perennials that fare well with a fall cutback are bearded iris, columbine, salvia, yarrow, peonies, and day lilies. But other perennials are best left alone until spring to prune.  For example, hostas, asters, and heucheras need their foliage for protection over the winter as do woody plants like lavender and Russian sage.

Plants in their dormant form can also provide garden interest and their dead flowers, fruit, seed pods, and foliage serve as sustenance or habitat for birds and beneficial insects. However, getting rid of dead or dying foliage on plants can discourage fungal growth, disease, and infestations. If you know a perennial has had fungus or other problems, remove infested parts, putting them in the trash rather than the compost, and clean your pruners with isopropyl alcohol after each use.

Timing can be tricky when cutting back your plants in the spring. Examine your plants carefully and do your cutting early enough to avoid damaging new growth, such as fern fiddleheads and the new shoots of ornamental grasses.

Pruning,perennial,plants,for,the,winter,with,a,secateurs.,a
March Tips:
  • While spring bulbs are ideally planted in early November or before the first hard frost, they may still bloom even if planted in early March. If you still have some unplanted bulbs, give them a try!
  • Veggies that can be direct sown outside in March when the soil is consistently at or above 40 degrees include peas, arugula, lettuces, mustards, and spinach. The soil temperature should be closer to 50 degrees to plant rhubarb and asparagus crowns, and leeks. Watch for the yellow blooms of forsythia. It’s a good signal that it’s time to prune your roses.
  • Plant your berry crops this month! If you haven’t pruned your blueberry bushes yet, best to do it soon. Typically they should be pruned anywhere from January to early March.
  • Your fruit trees are also best pruned during their dormant season, late winter to early March. deciduous shrubs and trees.as shown that you need lime.
  • Mulch all beds and insulate prized tender plants with cages filled with straw or leaves.
  • Help shrubs under house eaves avoid drought damage by watering them deeply every 6 to 8 weeks, but only when the air temperature is above freezing.

February 2022

Integrated Pest Management

Integrated Pest Management (IPM) is an effective and environmentally sensitive approach to pest management that relies on a combination of common-sense practices you can follow in your garden using these basic steps:

Monitor Regularly to identify pests.

Set Thresholds on how much damage you can tolerate.

Explore treatment options

Cultural Controls – Choose the right plants for your area. Know their light and water requirements and your soil pH. Select plants resistant to pests and disease. Native plants are more resistant. Weed and clear fallen leaves and debris from plant borders. Disinfect garden tools after using them on an infected plant.

Biological Controls — Adult lady beetles, green lacewing larvae, soldier beetles and assassin bugs are predatory insects that might be in your garden. They prey on some garden pests. Release lace wings and lady beetles.

Physical Controls – Weed, mulch, hand-pick or spray off pests with a hard stream from a hose; use sticky insect barriers.

Chemical Controls – Chemical controls kill pests but may also kill helpful predatory insects. Use the least toxic pesticide that targets only the identified pest: insecticidal soap and Neem oil (when pollinators are not present). Avoid broad-spectrum pesticides.

Evaluate Results by monitoring after treatment. Use no further treatments unless pests are again past your threshold limits.

Houseplant Copy
February Tips:
  • Yank or hoe annual weeds before they set seed. Remove all root parts to eradicate perennial weeds.
  • Cut deciduous ornamental grasses close to the ground at month’s end before new growth appears.
  • Give rhododendrons and azaleas their spring feeding and fruit trees when you see signs of new growth.
  • Finish planting/transplanting deciduous shrubs and trees.as shown that you need lime.
  • Mulch all beds and insulate prized tender plants with cages filled with straw or leaves.
  • Help shrubs under house eaves avoid drought damage by watering them deeply every 6 to 8 weeks, but only when the air temperature is above freezing.

January 2022

Planning Your Veggie Garden

Each winter as you begin planning next season’s veggie garden, you need to make some tough decisions on what fruits and vegetables to grow. One focus might be types that are highly perishable or expensive to purchase. Another is varieties that are difficult to find at your grocery or farmers’ market. A third might be foods that are extra good for your body or those that you eat frequently. And of course, it is always a good idea to choose varieties that grow best in our area.

You also need to consider your garden location and size.  Does it get at least 6 hours of sun?  What veggies can tolerate some shade?  How much space can you allocate for a vining plant? Is there a bush variety or can you grow vines on supports?  How long will your plant take to produce?  For example, winter squash need lots of room and 3+ months to mature.

Then develop your plan.  Plant things you know you’ll eat or can put up. Less is more – do you really need five zucchini plants?  Sequence your plantings so your harvest isn’t all at once but extended. Reseeding veggies like lettuces and radishes every few weeks can provide an ongoing supply. Finally, do a reality check:  how much time can you allocate to watering, watching for pests, harvesting, fertilizing, etc.?  Find more information here.


December 2021

Managing Excess Water

While our Pacific Northwest summers appear to be getting drier, the prediction is for more moisture during our wet season, especially as big dumps. Consider some of these changes to help manage excess water on your property.

Building a swale will redirect water drainage. Make sure, though, that it doesn’t direct flow toward your neighbors or directly off your property. Instead, make its focus a bed whose plants can handle extra water or a rain garden. Rain gardens provide a place for water to pool and can be vegetated with plants that can tolerate lots of moisture, like many PNW natives.

Less intensive solutions include diverting the water from your downspouts so it doesn’t puddle in one spot or collecting the water in rain barrels or cisterns for use during dry times. Another is using a heavier weight mulch that doesn’t float away. For vegetable gardens in wetter areas, consider building raised beds which will provide drier feet for your plants.

Finally, need a new driveway or walk? Consider using gravel instead of concrete which will allow rain to percolate into the soil rather than run off.

Januarytipsphoto
January Tips:
  • Regularly monitor your garden for pest damage, dislodged mulch, storm damage.
  • Use this time of less leaves and blooms to look over your garden and consider changes.
  • Use dormant sprays of lime sulfur or copper fungicide on roses for general disease control and spray peach trees with fungicides to combat peach leaf curl and shothole.
  • Now is the time to begin pruning non spring-blooming shrubs, but only if necessary.

Flooded,english,organic,garden,with,pools,and,ponds,of,water
December Tips:
  • Protect your compost pile from heavy rains to reduce loss of nutrients.
  • Adding a new garden bed? Turn the sod over now so the grass and weeds can decompose before spring.
  • If you put green kitchen waste in your compost bin, keep the bin fully enclosed and lidded to keep out rats.
  • When planting new trees or shrubs, don’t mound mulch against their base as it may encourage rodents and result in damage.

November 2021

Houseplant Care

With our gardens now mostly put to bed, November is a good month to focus on houseplants.  These may be year round indoor residents or tender plants that enjoy summers outdoors.  Light is the most critical factor.  Try to place plants as close as possible to windows so that they can avail themselves of our limited winter light. As the temperature next to windows may be too cool, keep a watch and consider adding supplemental light if plants need to be moved away a bit.

Rooms with high temperatures or locations next to heating vents can also cause problems for plants, as does incorrect watering. Hard dry soil can’t easily absorb water. For most houseplants, it is important to keep the soil evenly moist. Increasing humidity – by grouping plants, using a humidifier, or misting – can help. Plants that have outgrown their pots with more roots than soil, also have difficulty taking up water or nutrients.  They should be repotted this month before they go dormant.

Even plants that aren’t root bound need their soil replenished occasionally to continue thriving.   Be sure to use a soil meant for container plants – not regular garden soil – and water with a weak solution of water-soluble fertilizer just once a month during dormancy.  Find more houseplant information here.

Houseplant Copy
November Tips:
  • Finish planting all spring-blooming bulbs.
  • Apply dolomite if a soil test has shown that you need lime.
  • Mulch all beds and insulate prized tender plants with cages filled with straw or leaves.
  • Help shrubs under house eaves avoid drought damage by watering them deeply every 6 to 8 weeks, but only when the air temperature is above freezing.

October 2021

Dahlia End of Season Care

Your dahlia tubers may suffer during the winter months if left in the ground. Tubers that are not planted deep enough may freeze or they may rot if your soil does not drain well. Consider digging your tubers and storing them over the winter in a non-freezing location (40 to 45 degrees) such as a basement or garage. If possible, let plants grow until frost then cut stems down to 6 or 8 inches. After a week, (to let “eyes” develop) dig a foot away on all sides of each clump, then carefully lift out the fragile tubers. Hose off dirt and let them dry a day or two on a screen or table in your basement or garage before dividing them for storage. When dividing tubers look for eyes for next year’s growth and discard any rotted sections. Clip off skinny roots and tubers.

After division, many growers store their tubers in plastic bags filled with 1 to 2 cups of coarse vermiculite or pet bedding, and placed in cardboard boxes or brown paper bags until spring.

Throughout the process be sure to keep your dahlias labelled and to sterilize your cutting tools with a 10:1 solution of water to bleach before moving to the next plant or tuber.

Yellow Dahlias
October Tips:
  • Now is the time to divide herbaceous perennials but make sure your divisions have a hefty portion of roots.
  • Don’t cut back your perennials completely as leaving some standing growth provides protection from winter cold. Leaving seedheads will also provide food for wildlife and winter interest in your garden.
  • Be alert for signs of fungus. Put diseased materials in the trash rather than your compost.
  • To winter over potted geraniums and fuchsias, shear back and put in a cool, dark, nonfreezing place. Give them a cupful of water every month until March.

September 2021

Tent Caterpillars in Your Garden

Populations of tent caterpillars are usually held in check by winters cold, enough to kill many of the egg masses laid in the fall.  But a mild winter may mean a tent caterpillar heyday in the spring.  There are things you can do, however, to help mitigate the damage and mess they make out of your plants.  The larval stages of several moths and butterflies create tents, but the controls for these caterpillars are all the same.

The tent caterpillar life cycle begins in the fall with adults laying eggs on branch ends of plant hosts that leaf out in the spring and become food for the caterpillars.  The masses of hundreds of eggs are laid in a flat viscous material that dries hard and is camouflaged with the bark of the plant on which they are deposited.  It takes some hunting to find these masses, but once you develop an“eye”for them, many can be easily found, removed manually, and disposed of.

When caterpillars hatch, they set up a tent of webbing.  Each evening, they return to this tent for protection against the weather and predators. This is the best time to control them by removing the portion of the branch that contains the tent and dispose of it offsite.

For shrubs and trees that have branches out of reach, a bacterium Bacillus thurigensis  (Bt) can be applied to foliage early in the plant’s spring growth – ideally before the caterpillars hatch. Once caterpillars ingest the bacteria-coated foliage, they die in 24 to 48 hours. However, once caterpillars reach ¾ inch in length, the Bt does not seem to have the same amount of control.

Parasitic wasps and other natural enemies of the tent caterpillars can be used as well.  More potent chemicals are available but are not as safe for beneficial insects and animals. Additional questions?  Go to https://extension.wsu.edu/whatcom/hg/hg-plant-clinic/

Photos For Barbara
September Tips
  • Although spring blooming bulbs appear in stores this month, wait to plant them in late October, early November.
  • Don’t pick your ornamental gourds or winter squash too early.  Wait until the stems turn brown and the vines start dying.
  • Throughout the fall, keep prunings, fruit and other debris picked up so they don’t provide a home for pests and diseases
  • Early fall is a good time for seeding a new lawn or bare patches due to less weed competition, mild temperatures and fall rains.

August 2021

Plant a Cover Crop

Cover crops serve several valuable functions in the home vegetable garden.  The plants prevent erosion from winter rains and reduce the ability of weeds to grow.  They also help the soil retain nutrients for next season’s crops and can even fix nitrogen if you use legumes like crimson clover or field peas. Most commonly planted by gardeners in the fall, cold hardy cover crops serve as ‘green manure’, when cut and turned into the soil in the spring to decompose and increase organic matter.  However, cold sensitive cover crops can be used in warmer months to suppress weed growth in garden space that is not planted in the current year.  Planning for the use of cover crops is important – to determine the right time for good germination and which crop best suits your needs and the size of your gardening space. Go to these two WSU fact sheets for more detailed information:

Gardening west of the Cascades and Successful cover crop management.

Cover Crop Mix 2
August Tips:
  • Sow seeds of cool season leafy greens – lettuce, spinach, kale and chard – this month for harvest this fall.
  • Wait to transplant any ornamental shrubs or trees until after September. This is a very stressful time and doing so may result in the plant’s death by spring.
  • Powdery mildew is likely to appear on roses, apples, grapes, lilacs and annuals.  A fungicide will protect new growth but will not affect the mildew already there.
  • Avoid watering your tomatoes from above as moisture on the leaves can encourage a fungus known as late blight. Consider a plan to grow them under cover next year to protect them from rain as well. 

July 2021

Make Every Drip Count

As our PNW summers grow increasingly dry, it’s time to up your efforts to conserve water and make every drip count. The first rule is to water plants only when they need it and use water-miser methods. Use drip irrigation or soaker hoses and avoid sprinklers as they have significant water loss due to evaporation. Be sure to position the water devices you use to prevent water runoff into walkways, storm gutters or the street. In addition, for shrubs, trees and the lawn, remember the mantra to water deep and less often. Plant selection is key. Select drought-tolerant lawn grasses – or let your lawn brown out. Include more water-frugal plants, especially natives that are suited to our climate. And be sure to keep your beds mulched to retain soil moisture and remove weeds that steal water from your plants. Finally, consider ways to keep water on your lawn. Add rain barrels to collect rainwater for watering plants. Design a rain garden or develop a swale to retain water in your soil and prevent runoff. Investigate your local codes regarding the use of grey water.

Julytipsphoto
July Tips:
  • For the rest of the season, only feed your roses, flowering annuals and veggies.
  • The yield of beans and cucumbers is improved by watering a few times with a low-nitrogen liquid fertilizer.
  • Continue to deadhead your flowering plants and harvest your veggies when they are in prime condition.
  • Let your tomatoes ripen on the vine for best flavor – except later in the year when a frost is predicted.

June 2021

Common Pests in Summer

The pests in your garden enjoy your plants as much as you do. To eliminate them or reduce their numbers, avoid using broad-spectrum insecticides, when possible, to conserve the beneficial insects and birds that are their natural enemies.

Sticky leaves? A close look will reveal aphids – small pale white insects under leaves or on stems. These insects are drawn to new growth and can be promoted by an over vigorous feeding of nitrogen. Spray them with a strong stream of water.

Winding tunnels in the leaves of chard and other leafy greens? It’s most likely leaf miner. Pick and destroy affected leaves and, next year, cover your plants with fine screening or row cover.
Holes or whole sections missing in leaves of your Brassicas (kale, cabbage, broccoli, etc.)? Look for the cabbage worm, the larva of the white cabbage butterfly flitting around your garden. Hand pick the caterpillars, destroy any pupae, cover plants with floating row cover or screen cages to prevent egg-laying by the butterflies.
Tiny holes sprinkled across the leaves of beets, kale, collards, radish, and nearby weeds? Tiny brown/black flea beetles may be the culprit. Use floating row cover early in the season.

For more in-depth information about these and other garden pests go to WSU Hortsense.

Photos For Barbara
June Tips:
  • Give your rhododendrons their last feeding of the season before July 15 – or their first if you didn’t do it earlier.
  • If you decide not to let your lawn brown up to save water, then you will need to give it a deep watering of about an inch/week now that the rains are stopping.
  • Be sure to deadhead your perennials as they finish blooming or remove dead flowers from those that bloom all season. This prevents the plant from wasting energy by producing seeds.
  • If you don’t like dandelions in your lawn, the only effective way to eliminate them is to dig them out with their root.

May 2021

Make Your Tools Work for You

No matter the season, keeping your garden tools in good repair will pay dividends in time, effort and efficiency.  Never put your tools away dirty. Scrape or brush off dirt, quickly rinse with water then dry. If there are sticky spots – from sap perhaps – apply a few drops of a light multipurpose oil like 3 IN ONE oil, then wipe off. If there is rust, add a few drops of oil, scrub with steel wool  then wipe off. Once your tools are clean and rust free, sharpen if needed using a mill file or sharpening stone. Tool handles of unpainted wood also require maintenance. After sanding off any splinters, apply a coat – or more – of boiled linseed oil dependent upon how dry the wood is. For a quick and easy storage of your cleaned tools, or tools that haven’t gotten dirty during brief use, place them in a bucket filled with oiled sand.  This will keep them rust free.  Check the tire air pressure on garden carts and wheelbarrow with pneumatic tires and oil the wheel bearings for all wheels.

Two safety tips: 

  • When using your tools on diseased plants, spray them with isopropyl alcohol or bleach before moving to the next plant to avoid spreading disease.
  • Never pile your oily rags in a heap.  Hang to dry to prevent spontaneous combustion.
Tools May Garden Tips
May Tips:
  • Monitor aphids on strawberries and ornamentals. Control with water spray, hand removal, or registered insecticides labeled for the problem plant. Promote natural enemies (predators and parasitoids that eat or kill insects) for a longer-term solution.
  • Before mulching your beds, consider laying down a soaker hose to minimize the time you save watering, and to cut down on water usage. 
  • Watering slowly and deeply encourages your plants to build deeper root systems and lessens the need for frequent watering.
  • Prune your early flowering deciduous shrubs as they finish blooming. 

April 2021

Start a Pollinator Garden

One of three foods on your table depend on pollinators that include insects we all know: bees, butterflies, flies, wasps and beetles. But these pollinators cannot survive without nectar, pollen and host plants. 

Create a healthy environment for insect pollinators by providing a garden that blooms from early spring through late fall, plus adding plants that repel pests (marigolds, geraniums, lavenders and mint). There is no minimum size. All you need is a sunny area, a rocky bee-perch, water basin and pollinator plants. If you do not have a yard or space, add pollinator plants to containers on your patio, deck or balcony.  Equally important is avoiding insecticides and pesticides, which can kill bees as can plants from growers that use neonicotinoids.  Go to the Xerces.org to learn how to best protect your pollinators from these chemicals.  

For small gardens plant zinnia, sedum, aster, Joe-Pye weed, rue, liatris, parsley, chives, bee balm and goldenrod. For larger gardens plant campanula, catnip, chives, parsley, hyssop, lavender, sedum, native goldenrod, bee balm, rue, liatris, aster, sunflowers, scabiosa, coneflower (single petals), dahlias (single petals), black-eyed Susan, Joe-Pye weed and milkweed (Asclepias especiosa, Asclepias tuberosa and Asclepias incarnata). 

In your vegetable garden add companion plants that are good pollinators. Mix cosmos with cucumbers, basil with tomatoes and calendula with summer squash. Alyssum, bachelor’s button, bee balm, nasturtiums and rosemary are great additions, too. Plant dill, oregano, sage and thyme liberally. Bees and butterflies will love you if you let your herbs go to flower! 

pollinator-garden
April Tips:
  • Consider keeping a garden journal with frost dates, planting maps of your garden, seed and plant lists, successes and failures, photos, and other information that will make you a better gardener.
  • Allow the foliage of spring-blooming bulbs to brown and die down before removing as it manufactures food for next year’s blooms.
  • Wait until the soil temperature in your beds reaches 60 degrees to plant warm season vegetables.
  • If using slug bait, scatter it widely.  Encircling plants you want to protect will draw the slugs to them.
  • Delay mulching until the end of April, early May to let your beds warm up.

March 2021

Successful Seed Starting

Many gardeners like to start seeds indoors and a number of vegetable crops can be started in February and March for transplanting in spring.  One of the most frustrating diseases for gardeners when starting seeds indoors is “Damping Off” disease.  One day the tiny seedlings look great, the next day they are flat and dying.  Damping Off is a name given to several fungus diseases that attack the roots and stems of tiny plants. The best tip is avoiding, rather than trying, to treat the disease.  You do this by:

1. Thoroughly cleaning any reused trays and pots using soapy water, rinsing, spritzing with Hydrogen Peroxide, letting sit 20 minutes, then wiping dry;

2. Using seedling mixes instead of garden soil or potting soil which can harbor the disease.  Potting soils stay too wet and compact, inhibiting air exchange;

3. Watering seedlings from the bottom instead of over their tops and not saturating the soil;

4. Using a small oscillating fan to gently move the plants several hours per day to prevent the disease by drying out the top of the soil while strengthening plant stems.

The steps above will also help prevent the appearance of annoying soil fungus gnats whose larvae like to eat organic matter….including the tiny roots of seedlings!  

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March Tips:

  • Fill a unique pollinator niche in your garden with mason bees. https://catalog.extension.oregonstate.edu/sites/catalog/files/project/pdf/em9130.pdf
  • Finish pruning fruit trees, raspberries and summer and fall-blooming shrubs by the end of the  month. Wait to prune spring bloomers until their flowers fade.
  • A soil thermometer helps you know when to plant vegetables. Some cool season crops (onions, kale, lettuce, spinach) can be planted when soil is consistently at or above 40F.
  • Watch for pests and diseases. Hose off aphids; put out your favorite slug bait. Control rose diseases such as black spot by removing infected leaves and spraying as necessary with a registered fungicide.

February 2021

Prune to Control Regrowth

The two main seasons for pruning woody plants are late winter (dormancy) and midsummer (heading toward dormancy), though in temperate west-side Washington pruning for many plants can be done year round. As spring growth begins, many trees and shrubs respond by bursting new adventitious buds below the pruning cut. The replacement branches – water sprouts – are simply the plant replacing the leaf area it has lost through pruning. On some species cuts will trigger new shoots if you cut too much live wood in one season. With fruit trees, pruning during dormancy triggers speeds compartmentalization, healing, and regrowth. When cutting a larger branch (do not make cuts bigger than 4 inches) always cut back to a side branch that is 1/3 to 1/2 the size of that main branch. This is for the new growth to channel into. Otherwise the tree will respond by creating water sprouts which are difficult to control.

You can also curtail some of this physiological response by saving some of your cuts for after midsummer, July and August when the tree is switching to root growth and away from branch growth. And always mind the pruning budget: be careful to under, not over, prune. Never cut more than 1/4 of the leaf area and preferably 1/8 to 1/16. If you are restoring an older fruit tree, spread your cuts over several years. Also be careful not to strip smaller inside branches. These leaves are critical to tree health and strengthening all branches.

February tips:
  • A bumper crop of annual weeds appear in our gardens this month. Pull or hoe them before they set seed or they will only get worse.
  • If you want to know your soil’s pH or what nutrients you need to add to best support the plants you intend to grow, take a soil sample and get it analyzed. Find directions on how to do that and where to take your sample.
  • Your rhododendrons and azaleas – acid-loving spring bloomers – should be fertilized this month before they bloom. Be sure to follow package directions.
  • When garden soil is very wet, don’t work it or stand on it. You can damage the soil structure and compact it.
  • If you want to aerate or de-thatch your lawn, February and early March is a good time.

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