My occupation as a nursery manager means I am the recipient of many gifts throughout the year. Most of these come in clear, plastic baggies and they aren’t your typical offerings, as the usual fare includes weeds, spotted leaves, dead twigs, blighted fruit or insect specimens. Essentially, every time something bugs you in the garden you bring me your most wanted for identification and a plan of attack.
You may have noticed that many of the common pesticides and herbicides used in the past are no longer available. Now, you are being recommended new products (usually organic-based or lower impact) or an alternate means of control.
Additionally, local bylaws are restricting the use of cosmetic pesticides (such as lawn herbicides) and have banned the use of some products altogether. These changes, although not always easy to cope with, are here to stay and as gardeners we need to learn to accept some of the resulting plant blemishes and weeds as par for the course.
Take the Apple Scab (Venturia inaequalis) shown above.
For years now, we’ve been trying to grow our favourite Okanagan apples here with no regard as to whether they actually thrive in coastal weather (which they don’t) and we’ve tried to deal with the consequences by simply spraying every time a fungus takes hold. Now that most of these pesticides have been discontinued, many of us are left with some pretty unsightly trees and fruit, particularly after a wet spring which favours Apple Scab.
A better choice here would be to research which apple cultivars have been traditionally tolerant or specifically bred for our wetter climate, with a few good choices being ‘Jonafree’, ‘Redfree’, ‘Liberty’, ‘Freedom’ and ‘Prima’.
Cultural controls such as planting apples in areas with good soil drainage and air circulation will also go a long way to minimizing the impact of Apple Scab. Simple sanitation practices such as picking up fallen infected leaves or fruit and discarding (which breaks the life cycle) also helps, as does a dormant spray of lime sulfur and horticultural oil which minimizes winter fungi.
For those of you with existing trees you can still use readily available sulfur or copper-based fungicides to protect the foliage through the rainy spring season, although this approach is not always practical.
This brings us to yet another problem with giving pest control advice… that being you actually remembering what I said.
So to help you out I’ve set up a new website at www.mikesgardenguide.wordpress.com to help you deal with common fungal, weed or pest problems using organic-based (or low-impact) pesticides and cultural methods.
Please keep in mindthis is a work in progress as there are many potential pests out there – but you will already find detailed information on such problems as Peach Leaf Curl, Heuchera Rust, Currant Sawfly, Dogwood Anthracnose, Vine Weevils on Rhododendron, Black Spot on Roses and Photinia Leaf Spot.
Maybe you’ll bring me fewer bugs or blighted leaves in those plastic baggies, and hopefully replace them with an occasional homemade cookie, Canucks’ tickets or Granville Island Pale Ale (which I promise to enjoy it at home).
Mike Lascelle is a local nursery manager and gardening author. Email him at firstname.lastname@example.org.