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Planting in the Fall Makes Cents!

6 Sep

by Linda Kay Harrison

At the garden centers, we are often asked, “Is fall REALLY a good time to plant?”
The answer is… “Actually… yes!”

In the Pacific Northwest almost anytime is a good time to plant; but there really ARE some very good reasons to do it in the fall.

When new plants are installed in the spring or summer they have to go through the stressful heat of the summer with a small root system.  They are often expected to bloom and sometimes even produce fruit under these stressful conditions. That can take a lot out of a young plant.

By filling your beds in the fall, your plants miss out on most of that stress. With the days being shorter, photosynthesis slows and stops, so plants aren’t actively growing. They go dormant and often don’t even know they’ve been moved.  Even though the air is cooler, the ground is still warm, so the roots keep growing for weeks or even months without having to produce nutrition for growth or blooming. By the time your plants ‘wake up’ in the spring, their roots are strong and pretty well established in their new home.

You’ll also want to plant with plenty of Black Forest compost to break up that nasty clay soil, and give the roots something to work with over the winter.

One more great reason to plant in the fall… BARGAINS!  Even though the selection may be smaller, the sales and specials are fantastic!  You can save a lot of dollars, and that makes a lot of ‘cents’.

So when you tuck those plants into their beds for the winter, you can feel confident knowing that you saved a bundle, and your new plants will ‘wake up’ happy and ready to grow in spring.


Anti-Mosquito Tips For Your Yard

13 Jul

By Linda Kay Harrison

There are few things in life that are as enjoyable and memorable as a warm summer evening out in the backyard,… and there is nothing that can ruin one as quickly as mosquitoes. Nothing sends us running indoors quite like that annoying little buzz in our ears that we know will turn into itchy welts later.

The reality is that mosquitoes are more than just annoying.  Mosquitoes carry many diseases that can cause serious health issues.  So how do you go about driving away these tiny pests once they’ve made their appearance?

Here are some great ‘environmentally low-impact’ tips:

  • Start by checking your yard for any sources standing water.  Female mosquitoes can lay up to 300 eggs at a time, and do so in multiple water filled locations.  Sources of standing water can be ponds, birdbaths, flower pots and sauces, kiddie pools, the dog’s water dish, even low spots in your lawn
    • For ponds that you can’t drain weekly use mosquito dunks that are safe for fish and plants.  You can also use a product that contains Bacillus Thuringiensis, BT, which is a bacteria that kills mosquito larvae, but will not do harm to animals or humans.  Dennis’ 7 Dees has both of these products.
    • You might also add a spitter or fountain head to create movement in the water.  Mosquitoes use standing water to incubate eggs.
    • Stock your pond with fish that eat mosquito larvae like Shubunkins, Koi and Sarasa Comets.  These fish can eat up to 500 mosquito larvae a day.
    • Attract birds to your yard. A good bird population can make a huge difference in mosquito population. Many common backyard birds eat mosquitoes, so try putting out a bird feeder and a bird house. Don’t forget the hummingbird feeder. Over 10% of a hummingbird’s diet is small insects like mosquitoes.
  • Although some might say they’d rather have the mosquitoes, attracting bats to your yard is an excellent way to get rid of mosquitoes.  One bat can eat up to 600 mosquitoes in one hour! That’s a good reason to consider putting a bat house in your yard!
  • There are several plants you can use in your landscape and patio pots that will help you get rid of  mosquitoes naturally.  And most are beautiful and low maintenance.
  • Try planting crocosmia, monarda, fuchsia, honeysuckle and trumpet vine to attract hummingbirds.
  • Echinacea, coreopsis, and sunflowers attract finches and other insect-eating birds to your yard.
  • Some plants repel mosquitoes with their scent. Sassafras and sweet basil repel mosquitoes for short distances, so these are good choices for the pots in and around seating areas, decks and patios.
  • Other plants you might use for their repellant qualities are:
    • Citronella Grass (Cymbopogon nardus)
    • Catnip (Nepeta cataria)
    • Peppermint (Mentha piperita)
    • Rosemary (Rosmarinus officinalis)
    • Marigolds (Tagetes spp.)
    • Lemon balm (Melissa officinalis)
    • Garlic (Allium sativum)
    • Clove (Syzygium aromaticum)
    • Eucalyptus (Eucalyptus spp.)
    • Lavendar (Lavandula angustifolia )

If you’re just itching to get outside, don’t let mosquitoes spoil the fun! Instead, let the knowledgeable staff at Dennis’ 7 Dees help you find everything you need to take back your yard this summer!

Vacation Garden Preparation

27 Jun

You may have spent weeks, months or even longer planning for your trip.  Arrangements have been made for the pets, the newspaper and mail put on hold, your calendar is clear and you are ready to go!  Can your houseplants survive without you?  How long can your vegetable garden, patio containers and hanging baskets go without getting watered?

If you are fortunate enough to have summer vacation plans in your future you should be looking forward to some well-deserved and much needed relaxation.  Studies have shown that vacations are good for your health (and I would have to agree).  Leaving one’s home  however, can be stressful.   Preparing your home for a prolonged absence requires some strategic planning, especially if you have plants and/or pets that are staying behind.

Many well-watered houseplants will last for days to perhaps a week on their own.  If you’re heading out for only a few days, give them a final drink just before you leave and move them out of sunny windows or hot locations.  Outdoor potted plants will dry out faster, so give them a good soaking before moving them into a cool garage, basement or laundry room to slow down their water use.  If you have lawn sprinklers that are on automatic timers you can take advantage of them by moving your outdoor potted plants into an area where they will get watered when your lawn does.

Let’s assume your vacation is for longer than a week (to somewhere fabulous, of course).   How can you prevent your plants from suffering the consequences?  You really don’t want to be laying on that tropical beach wondering and stressing about your favorite hanging begonia basket!

Now that school is out and summer has officially begun, come learn how to prepare your garden for vacation.  If you love your plants, it will be well worth your while to spend a little time with our expert vacationer, Nicole.  She will share with you her tales of disappointment and triumphant stories as well as discuss what happens to your garden while you are away on that Alaskan hiking trip of your dreams…

You will learn of several methods to keep plants watered, as well as products to assist plants during periods of drought stress. She will also give you tips and techniques to avoid major disappointment upon your homecoming; returning from vacation is hard enough as it is!

“Vacation Garden Preparation” June 30th @ Cedar Hills 10 am *

“Vacation Garden Preparation” June 30th @ Lake Oswego 1 pm *

“Vacation Garden Preparation” June 30th @ SE Powell 3 pm *

Shade Gardening

21 May

In an area with an abundance of trees, one of the biggest challenges for gardeners is that with them comes shade. Generally, a partially shaded area is one that receives 3-6 hours of direct sunlight daily. Wet, dry and deep shades are the most common planting situations in our area.

We usually encounter wet shade in areas with poor drainage and edges of bogs, ponds or streams. Under conifers (i.e. Douglas Fir) and deciduous trees (i.e. maples) is where we most often encounter dry shade. In a dry shade situation, new plants must compete for water with the established trees. Deep (or full) shade is an area that receives less than 3 hours (and perhaps only dappled) direct or indirect sunlight daily. A garden bed on the north side of a house is considered deep shade.

Because the above-mentioned shade situations present particular challenges, choosing plants best suited to the situation results in smart gardening. Along with tips for success, below are lists of some plants that thrive in various shade situations.

To assist with heavy soil plagued by poor drainage, always mix compost with the existing soil prior to planting. Products such as Turface also aid in improved aeration. The following are some plants suitable for wet shade:



    • Muscari/Grape Hyacinth—grass-like green foliage, fragrant flowers of varying colors in spring, will naturalize if undisturbed
    • Crocus/Crocus—fine green foliage, varying colors patterns of flowers, bloom in spring or fall
    • Galanthus nivalis/Snowdrop—nodding white w/green accents flowers held above grass-like foliage in spring, will naturalize if left undisturbed
    • Narcissus ssp./Daffodil—narrow bright green foliage, flowers are usually shades of yellow, bloom in spring, can be used in borders or to naturalize


    • Soleirolia soleirolii/Baby’s Tears—tiny foliage, spreads by creeping stems, vigorous
    • Pachysandra terminalis/Japanese Spurge—evergreen, spreads by shallow underground roots, clean-looking foliage
    • Houttuynia cordata ‘Chameleon’/Chameleon Plant—splashes of cream, pink, yellow and red on heart-shaped foliage, tiny white flowers that resemble those of a dogwood, monitor growth—can be aggressive in very wet areas (spreads by underground stems), dormant in winter
    • Lamium/Dead Nettle—evergreen in mild climates, heart shaped foliage, vigorous growth
    • Vinca minor/Dwarf Periwinkle—evergreen, trailing, roots where arching stems touch the ground, star-like flowers in blue, white, mauve or deep purple


    • Acorus/Sweet Flag– evergreen grass-like
    • Astilbe/False Spirea—summer blooms of varying color with file-textured foliage, dormant in winter
    • Carex/Sedge—many are evergreen, foliage is soft looking and feeling
    • Filipendula/Meadowsweet—summer blooms held above coarsely divided foliage, dormant in winter
    • Juncus/Rush—tolerates standing water, grass-like appearance
    • Myosotis/Forget-Me-Not—spring blooms of blue, white or pink held above dark green foliage, can be used as groundcover, dormant in winter
    • Zantedeschia/Calla lily—shiny arrow-shaped foliage, white flowers, dormant in winter

Shrubs and Trees:

    • Clethera alnifolia/Summersweet—deciduous, fragrant spikes of white flowers late summer/early fall
    • Vine Maple

      Gaultheria shallon/Salal—evergreen, glossy, nearly round green foliage, white or pinkish bellshaped flowers followed by edible berries, NATIVE

    • Cornus stolonifera/Redtwig Dogwood—deciduous, fast-growing, green or variegated foliage, brilliant red stems in winter, NATIVE
    • Acer circinatum/Vine Maple—deciduous, many-stemmed, mulit-trunked large shrub/small tree, nearly round light green foliage that turns orange, yellow or scarlet in fall, NATIVE
    • Sequoia sempervirens/Coast Redwood—evergreen, fast-growing, feathery foliage, reddishbrown bark, pyramidal mature shape, NATIVE


Winter and early spring are optimal time frames to establish new plantings in dry shade, as it is at this time when such areas receive periods of moisture. New plants are thereby allowed to settle and develop a good root structure prior to entering into their growth stage. Likewise, if planting in the heat of summer, you will have the greatest success by providing regular water to newly planted areas. Products such as Turface worked into the soil at planting time can assist with water retention. The following are some plants suitable to dry shade:


    • Crocus/Crocus—fine green foliage, varying colors patterns of flowers, bloom in spring or fall
    • Fritellaria imperialis/Crown Imperial—broad, glossy green foliage supports talk, sturdy stalk topped with red, orange or yellow bell-shaped flowers tufted with green leaves
    • Galanthus nivalis/Snowdrop—nodding white w/green accents flowers held above grass-like foliage in spring, will naturalize if left undisturbed
    • Narcissus./Daffodil—narrow bright green foliage, flowers are usually shades of yellow, bloom in spring, can be used in borders or to naturalize


    • Cyclamen hderifolium/Baby or Hardy Cyclamen—triangular to heart-shaped deep green marbled with silver, star-shaped fragrant flowers of white or pink in late summer/early autumn
    • Epimedium/Bishop’s Hat—semi-evergreen to evergreen heart-shaped foliage, stalks of little flowers of white, pink, red or yellow in spring
    • Gaultheria shallon/Salal—evergreen, glossy, nearly round green foliage, white or pinkish bellshaped flowers followed by edible berries, NATIVE
    • Mahonia repens/Creeping Oregon Grape—evergreen, blue-green foliage turns spectacular purply-bronze with cold weather, clusters of small flowers in mid to late spring followed by dark blue berries, NATIVE
    • Sarcoccoca/Sweet Box—evergreen, small, fragrant winter/early spring flowers


    • Hellebore

      Alchamilla/Lady’s Mantle—roundish lobed foliage of pale green, clusters of yellow flowers in summer

    • Bergenia/Pigsqueak—evergreen, rosette of bold, glossy foliage, pink or white flowers in spring
    • Helleborus/Hellebore—evergreen, long, leathery, leaflets, cup-shaped flowers of white, green, pinks, purples in winter through spring (note: they do NOT like being transplanted!)
    • Heuchera ‘Creme Brulee’

      Heuchera/Coral Bells—evergreen, roundish foliage with scalloped edges, available in a variety of colors (yellows & limes in particular appreciate and brighten a shady spot in the garden!), spikes of delicate flowers in spring or summer

    • Lirope/Lily Turf—evergreen, grass-like straps of green foliage, spikes of white or purple flowers in summer

Shrubs and Trees:

Evergreen Huckleberry

    • Acer circinatum/Vine Maple—deciduous, many-stemmed, mulit-trunked large shrub/small tree, nearly round light green foliage that turns orange, yellow or scarlet in fall, NATIVE
    • Calocedrus deccurens/Incense Cedar—evergreen, large, pyramidal, flat sprays of rich green foliage, reddish-brown bark, lovely fragrance, NATIVE
    • Hydrangea queciifolia/Oakleaf Hydrangea—deciduous, large, deeply-lobed foliage that resembles (in shape) oak leaves, exquisite bronze to red autumn color, long clusters of white flowers in late spring/early summer,
    • Kalmia latifolia/Mountain Laurel—evergreen, leathery, oval, glossy green foliage, pink, white or red flowers in spring, slow-growing
    • Vaccinium ovatum/Evergreen Huckleberry—evergreen, shiny, toothed, dark green foliage tinged w/red when new, white or pink flowers followed by edible black berries in summer, NATIVE
    • Mahonia aquifolium/Oregon Grape—evergreen, glossy green leaflets that resemble (in shape) holly leaves, new growth tinged red and take on purplish color with cold, yellow flowers in spring followed by edible blue-black fruit in summer, NATIVE


In areas that receive little to no direct sun, or only minimal dappled sun soil also needs special consideration. As with soil in wet shade, the goal is to improve drainage to allow greater planting success. Adding compost to existing soil is a must in these areas. The following are some plants suitable to deep shade:


    • Arum/Jack-in-the-Pulpit—foliage emerges in fall or winter and is green with white veins and arrow-shaped, calla-like “flowers” emerge after foliage and are followed by clusters of red berries that persist after foliage dies (actually a tuber)
    • Colchicum/Meadow Saffron or Autumn Crocus—broad green foliage in spring that die down in late summer/early autumn when flaring white, rosey-purple or lavender-pink flowers bloom (actually a corm)


    • Cornus canadensis/Bunchberry
    • Epimedium/Bishop’s Hat—semi-evergreen to evergreen heart-shaped foliage, stalks of little flowers of white, pink, red or yellow in spring

      epimedium flower

    • Gaultheria procumbens/Winterberry—evergreen, small dark green foliage that clusters at the end of a stalk, strong wintergreen fragrance when bruised, pinkish flowers in spring followed by red berries that persist through winter
    • Pachysandra terminalis/Japanese Spurge—evergreen, spreads by shallow underground roots, clean-looking foliage
    • Sarcoccoca/Sweet Box—evergreen, small, fragrant winter/early spring flowers
    • Vinca minor/Dwarf Periwinkle—evergreen, trailing, roots where arching stems touch the ground, star-like flowers in blue, white, mauve or deep purple


    • Anemone/Wind Flower—clumped foliage gives rise to tall, graceful stems that are topped with single or semi-double white or pink flowers in early autumn
    • Fern

      Brunnera macrophylla/False Forget-Me-Not, Brunnera—large, heart-shaped foliage of green or silver veined with green, dainty blue flowers rise above foliage spring into summer

    • Ferns—LARGE family of plants, deciduous, semi-evergreen or evergreen, vary greatly in size and look of foliage
    • Hosta/Plantain Lily—clumps of lance-shaped to nearly round foliage of many different colors and patterns, mature size varies greatly in this group, spikes of trumpet-like blue or white flowers in summer (some are fragrant)
    • Hosta

      Corydalis/Corydalis—clumps of finely lobed, fern-like foliage, clusters of spurred yellow, blue (many variations of blue) flowers spring into summer

    • Ophiopogon/Mondo Grass—evergreen, small, grass-like foliage of green or black, stems of small, clustered purple flowers in summer followed by black berries
    • Trillium/Wake Robin—multi-stemmed, low-growing woodland plant, each stem holds a whorl of 3 leaves topped by a 3-petaled flower in early spring, goes dormant in mid to late summer

Shrubs and Trees:

    • Tsuga – mountain hemlock

      Acer circinatum/Vine Maple—deciduous, many-stemmed, mulit-trunked large shrub/small tree, nearly round light green foliage that turns orange, yellow or scarlet in fall, NATIVE

    • Aucuba japonica/Japanese Aucuba—evergreen, smooth green or green splashed w/yellow foliage, sparkles in deep shade!
    • Fatsia japonica/Japanese Aralia—evergreen, large fan-like glossy dark green foliage, tropical looking
    • Kerria japonica/Kerria—deciduous, toothed and crinkled looking, triangular, bright green foliage, single or double rose-like small yellow flowers in spring
    • Tsuga/Hemlock—evergreen, horizontal needle-like sprays of foliage, graceful, large group of conifers that range in size and habit, NATIVE (Mountain and Western Hemlocks)

Beneficial Insects – Pollinators, Predators & Parasites

18 May


In any well-balanced ecosystem there are pests and natural enemies. For this reason, some pests do need to be present in the environment for natural enemies (i.e. insects we consider ‘beneficial’) to continue to survive. In a garden, a pest is an insect that feeds on and/or transmits disease to desired garden plants, whereas beneficial insects work to maintain the ecosystem balance by consuming their natural enemies. There are three types of beneficial insects:
Pollinators—not only do many bee and fly species pollinate plants, they also eat and/or destroy many ‘bad bugs’ in the landscape.
Predators—some insects are predaceous in their larval stage, others as adults, yet others as both larvae and adult. Additionally, some have a diverse diet, and others such as ladybugs, eat only a certain type of food source (aphids in the case of the ladybug).
Parasitoides—these are insects that live on or in a host insect so they can feed on it, usually killing it in the process. Many are parasitic fly or wasp species that inject their eggs into the host. The eggs hatch then transform into larvae, and because they’re within the host insect, they have a natural food source immediately available.


How do you attract beneficial insects to your garden? Create a diverse environment in your landscape. It’s that simple. What does that mean exactly? A diverse garden is one planted with a mixture of plants, having varied bloom time, flower shape, and size all inter-planted with one another. An example would be planting vegetables and companion flowers such as marigolds, cosmos and nasturtium. Did you know that planting garlic with peas, lettuce and celery will help keep aphids away from your crop?
All beneficial insects require a reliable food source, and for some of them it is specific. When creating your palette remember our beautiful native plants—many wonderful bugs depend on them! The following is a sample list of insectary plants that specifically attract and keep beneficial insects in the garden.

Sweet alyssum/Lobularia maritima
Lipine/Lupinus spp.
Sunflower/Helianthus annuus
Yarrow/Achillea spp.
Coreopsios/Coreopsis spp.
Cosmos/Cosmos bipinnatus
Candytuft/Iberis umbellate
Goldenrod/Solidago altissima
Marigold/Tagetes spp.
White lace flower or bishop’s weed/Ammi majus
Dianthus/Dianthus spp.
Lilyturf/Lirope spicata
Phlox/Phlox spp.
Blazing star or gayfeather/Liatris spp.
Zinnia/Zinnia spp.
Daisy/Belllis perennis and Leucanthemum spp.
Angelica/Angelica supp.

Buttertfly weed/Ascelpias tuberosa
Bugleweed/Ajuga reptans
Wallflower/Erysimum linifolium
Pincushion flower/Scabiosa columbaria
Joe Pye weed/Eupatorium purpureum


“Integrated Pest Management (IPM) is a strategy to prevent and suppress pests with minimum impact on human health, the environment and nontarget organisms.” –Steve Dreistadt, University of California
The focus of this systematic approach to pest management is prevention. Rather than waiting for a problem to arise in the garden, we can look at our garden ecology holistically. By monitoring pest populations and identifying pests if and when they do occur, we can then choose a combination of methods to keep things in check; acceptable levels are what we’re after, since complete obliteration is, in most cases, just not feasible. Keep in mind that 90% of the insects found in an average home garden are either benign or beneficial, leaving only the remaining 10% to be called “bad bugs.” Do your research; even bad bugs may have a function you may not necessarily want to attempt to eliminate. The primary premise stressed by IPM is to use the least toxic methods first! Some approaches may include cultural (i.e. keeping the garden clean), biological (i.e. use of beneficial insects— see table below), mechanical (i.e. physically block, trap or remove pests), and chemical (i.e. insecticidal soaps). Tactics vary from garden to garden. Share your approaches, successful and not, with fellow gardeners—all stand to benefit for healthier, more productive gardens.


Because most insecticides are “broad spectrum,” meaning they kill a wide variety of insects, beneficial insects are extremely vulnerable. Should you decide to use insecticides in your home landscape, great precaution must be taken to protect beneficial insect populations.

  •  Whether natural or chemical-based, choose the least toxic product available for the situation.
  • Spray only the area(s) on the plant that are affected
  • Spray when many insects are less active: early in the day (dawn or very early morning)
  •  Do not spray plants that are in bloom!

In sum, once you choose to use beneficial insects in your garden, protect their survival by not using insecticides unless absolutely necessary. Call or come in to your local Dennis’ Seven Dees Garden Center—knowledgeable staff may have alternative suggestions for you!


Decollate Snails – These pointed-shell snails eat brown garden snails

Earthworms – Soil aeration, speeds decomposition process, improves root growth & water retention; waste is considered one of the best organic fertilizers. Most active when temperatures are around 70°F, otherwise any time soil not frozen. Many types of worms will work in the garden—red wigglers, night crawlers, garden worms are all great!

Ladybugs – Eat many garden pests, are attractive, fun for children. Release ladybugs in the evening—they don’t fly at night.

Mason Bees – Increase pollination rates, specifically for early spring fruit trees.  Bees are usually sold in larval stage.

Nematodes – Effective against soilborne & wood-boring pests, pests that life part of their life cycle in the soil. Apply anytime when the soil is not frozen. Application lasts 2 years. Do not expose them to sunlight; suspend them in water to help them transport themselves.

Praying Mantis – Voracious eater in the garden. They’ll eat any insect they can catch— even other mandtids and beneficial insects! Very effective against aphids, beetles, caterpillars, grubs and grasshoppers late spring through summer. Usually sold in egg cases to be suspended in the garden; hundreds of insects hatch from each casing.

Lacewings – Eat many garden pests (up to 100 aphids per day!).  Sold as eggs, pupae, or larvae. If eggs are purchased, once they’ve hatched they must immediately be released AND there must be available food. With no food source(s) the larvae turn aggressive & eat one another.

Good Bug, Bad Bug (2008) by Jessica Walliser
Oregon State Extension Services: (this is a wonderful
resource—many articles available regarding this subject, as well as many others)
WSU Clark County Extension:
(another wonderful resource)
Xerces Society:

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