Resilient Gardens for a Changing Climate; workshop: Pest Control

Presentation: Resilient Gardens for a Changing Climate

“The new normal is no normal!” Last summer was the driest on record. Well respected,  year round Saltspring organic food gardener, Linda Gilkeson ( spoke about present gardening challenges and coping strategies.

– Mulch, mulch, mulch: it really works to cool plants, conserve moisture (and water bills!) and lessen weeds. Linda uses anything she can to mulch: shredded newspapers, straw, even burlap.  The best is compost/leaf mold.

– Shade: Linda shades new plants and seedlings in hot weather with remay cloches or tents. A newly seeded crop may need a layer of newspaper, burlap or plastic over it until it sprouts to keep the soil damp.

– It’s best to plant ornamentals in the fall before the rains (October) or in early spring. Keep them watered well for the first year or two. Look for drought tolerant and less tender varieties. Don’t bother with species that need constant moisture unless you have a natural bog or are willing to water a lot.

– Don’t buy plants that are already stressed (pot bound, diseased, drought stressed)

– Plant windbreaks and use natural micro-climates for protection

– Try different cultivars and seed strains to see what works best. Talk to your neighbours.  Look for strains that flower not too early and fruit not too late.  Sometimes the old tried and true standards and heritage seeds/strains are best.

– Choose cultivars that are disease resistant when you can find them.

–  Lawns: mow high, let clippings fall into lawn, water deeply but not often to promote deeper roots. Let dormancy set in over summer by watering even less.  Use a tougher and more drought tolerant lawn seed: “Fleur de Lawn’, with micro-clover

– Greenhouses and coldframes can overheat; be very careful to not ‘cook’ your plants in hot weather. Keep watered and ventilated. Fans may be necessary to prevent mildews.

– Collect ‘gray’ water from your kitchen and tub or shower.

– Check your garden soil to see how dry it is: dig under mulch or into the top layer.  Note that shady and mulched areas won’t need watering as much as exposed, sunny areas.  Under eaves and tree canopies, and beside concrete, will dry out faster.  Use sunny areas to plant sun-loving, drought tolerant plants: herbs, bulbs, or meadow flowers.

– If using an irrigation system, get familiar with it: check continually to ensure all areas are being watered, and that all of the system is functioning as it should.

– Potted plants need watering more often: smaller pots, and unglazed clay/concrete dry out even faster, especially if placed on hot, sunny patios/decks.

– Even moisture is best for seedlings, young plants and flowering (setting fruit)and fruiting plants, to avoid misshapen fruit and diseased crops

– Drainage is crucial for most plants (except bog plants). With the increased frequency of torrential rains, it is important to pay attention to your soil type. All soils benefit from the addition of annual compost mulch. If your soil is heavy clay, or your garden is in a dip, you may need to improve drainage with drain tiles, or creating a rain garden to collect heavy rainfall, or digging  ‘French drains’.

Workshop:  Organic Management of Garden Pests and Diseases

Linda Gilkeson –

The key to addressing disease and insects in both ornamental plants and food production is prevention. Stressed plants are more susceptible to attack because they are preferred by sucking and boring insects. Most plant problems are disorders resulting from poor growing conditions – nutrient deficiencies, injury, water-logged soil, poor soil quality, unbalanced PH, irregular watering, drought and temperature extremes.

Helpful Tips:

* Don’t bring home problems from the nursery. Some common insects that could be introduced into your garden are: viburnum weevil, leaf beetles, black vine weevil, camellia scale, soft brown scale, mealy bugs & spider mites.

* Inspect plants closely before purchasing:  Slide the root ball out of the pot to look for weevil larvae and check the undersides of leaves and along twigs.

* Before purchasing plants plan ahead by researching insect and disease resistant plants, choosing plants known to be rust, powdery mildew and black spot resistant.  Some varieties of peas can develop enation mosaic virus and powdery mildew to which roses are also susceptible.  Plants that have leaves with rolled edge margins prevent small insects from chewing them.  Frost Peach is a variety that has resistance to leaf curl.

* Quarantine new purchases for a while before putting out in the garden to see if anything develops that you don’t want.

* Change the disease-causing environment, for instance provide good ventilation and pruning to reduce infection (e.g. grow tomatoes in a well-ventilated tunnel to prevent late blight infection; keep peach branches dry in February to avoid leaf curl; cucumbers and melons can be protected by raising them off the ground; overheat cold frames and greenhouses between crops to destroy insects and disease.


Most insects you find in the garden are not pests. Most “are on your side” so learn which are the beneficials and encourage and protect them. The more we can keep the garden eco-system intact the fewer problems we will have.

Common insects:

* Leaf minors lay eggs on spinach, chard and, lettuce.   They come in waves and the lady beetles come in and clean up the eggs.

* Pea leaf weevil: This very tiny flying insect makes notches on the leaves and eats the nitrogen nodules causing peas to lose their nitrogen advantage. A serious infestation could result in the need to add nitrogen.

*  Pill bugs attack pole beans. They like the starchy seeds so starting plants ahead and putting them in the garden when they are larger will avoid pill bug damage because their tiny mouths prevent them from eating older plant parts.

*  Rose sawfly:  damage creates skeletonizing.  They only last a short while and then are gone so if not doing too much damage they can be ignored.  If causing a problem you can wash them off with a water spray.

* Wireworms (click beetles) bore into bulbs, tubers, roots, corms and large seeds.  Use potato traps, trap crops and possibly a newly developed Light Trap from P.E.I.  Fall rye attracts these beetles so do not rotate potatoes following a grass cover crop or where a lawn has been newly dug up.

* Spotted wing drosophila: This invader has become a highly destructive pest.  This is a fruit fly quite different from our regular compost bucket fruit flies that lay their eggs on rotted fruit.  This spotted wing variety can be identified by a black spot on the tips of the wings of the males.  It favours fresh soft-skinned fruit (e.g. raspberries, cherries, blackberries, blueberries, grapes). This makes it a serious problem with few options for control.  They saw through fruit skin to deposit eggs up to a month before fruit ripens. The maggots eat the fruit and then drop off to the soil. With a life cycle of 1-2 weeks the result is many generations over the course of the summer with the main infestations being July and August.

Spotted wing drosophila prevention:

  • Find out when they are turning up by making a trap by punching holes around the rim of a clear deli container and adding apple cider vinegar to attract them.
  • Choose early berry varieties.
  • Cover plants or fruit with netting 3-4 weeks before fruit ripens. Proteck Net holds up well. (The raspberry brazelberry called Shortcake is a low plant and easy to cover).
  • Pick overripe or unused fruit and destroy it.

Note:  some jurisdictions are reversing bans on Malathion to deal with this problem so beware when purchasing soft fruits.

* Dysdera (woodlouse) spiders are a treasure in the garden because they eat pill bugs.

* Ten-line June beetle – our natural June beetle – are usually temporary and not that common. They feed on roots of grasses and lawns but do little damage.

Find much more information at

Resilient Gardens 2016:  Climate change, stress disorders, pest update is available to purchase for $20.00 + GST.  Send order to Linda Gilkeson – P.O. Box 648 Salt Spring Island, BC V8K 2W2.