Wet Soil, Cool Crops and Pollinator Plantings

Our cold spring continues…with the soil too soggy to work in many gardens, especially after this recent heavy rain. If you squeeze a small handful of soil and it stays together in a compact clod, then it is too wet to handle; it should be moist but still easy to crumble apart after you squeeze it. Trying to turn in amendments in wet soil compacts the soil and crushes the air spaces that let in oxygen and let out carbon dioxide (plant roots, soil microbes, earthworms, etc. all need to breath). If hard clods form when your soil dries out, it is a sign of compaction, often seen in clay soils. Wait until such soil are drier before handling them and keep adding compost and organic matter from mulches to improve soil structure.

Gardeners are always eager to get out there and plant something, but really, there is no rush, especially if have crops in the ground year round. If you are not harvesting lots of overwintered crops right now (including all kinds of root crops, spinach, kale and leafy greens, broccoli, cauliflower, Brussels sprouts, cabbage), then plan to grow them this year so you can enjoy fresh harvests through winter and next spring. The more overwintered crops you have, the less you need to bother with seeds or seedlings while spring conditions are still wet and cool. This planting chart can remind you when to sow your winter crops at the right time.

It is time to dig up remaining root crops and put them in the refrigerator before they start growing. They lose flavour as they use up the sugars stored in their roots and will develop eventually develop a tough a flower stalk. There is no need to harvest leeks, however, because their flower stalk is tender and edible; it is also easy to remove from the centre of the leek when you are cutting it up. And don’t be in a hurry to clean out the Brussels sprouts plants. Even if yours never produced sprouts or if you have already harvested all of the sprouts, the plants are now growing tender and tasty side shoots all along the stem.

March Harvest

In warmer gardens when the soil is dry enough to handle, you can sow hardier vegetables directly in the ground (peas, lettuce, cabbage family greens, broccoli, cabbage). You can also plant potatoes and onion sets (it might be a good idea to hold off on planting onion and leek seedlings for a little longer). To hasten planting day, warm up and dry out a planting bed for a week or two before sowing by raking off any mulch (remove weeds, too) and laying a sheet of clear plastic on the soil. Or set a coldframe over the bed to warm it. Vegetable seedlings planted out now will fare much better than seeds will. Seeds need warmer temperatures for prompt germination than the same plants need for growth. Although hardy veggies are able to germinate at lower temperatures, it takes much longer, and leaves them vulnerable to disease and pests longer, than if you waited another week or two for warmer weather. Nurseries are stocked with veggie starts and on Salt Spring, Chorus Frog Farm on Rainbow Road, has a good selection of cool weather vegetables, herbs and flowers available.

Beware of climbing cutworms (caterpillars of the Large Yellow Underwing Moth), which are still doing a lot of damage. They are reaching maximum size so they eat a lot every night, chewing large ragged holes in leaves and making little seedlings disappear. Go out just after dark with a flashlight and look for fat caterpillers feeding on the leaves (they hide during the day). We have a few more weeks of attack before the cutworms transform into the pupa stage, usually around the end of April to early May. Plant damage stops as soon as the caterpillars pupate, which is another reason to sow seeds later to escape damage. The moths emerge later in the summer from the pupa (which are dark brown and bullet-shaped). See photos of all stages. There are other ‘cutworm’ species in the region that zip seedlings off right at the soil line. These are not usually as common as the LYUM climbing cutworms, but if your seedlings are cut and toppled in the morning, look in the soil right around the stems of damaged plants for fat, curled up caterpillars. For this type of cutworm, you can install collars to protect the stems of small plants at transplanting time. Collars should be an inch or two in diameter, 3-4 inches long. Bury the bottom end an inch deep in the soil so that it extends a couple of inches above the soil line. Cardboard toilet paper rolls, pieces of lightweight card stapled into a tube, small tin cans with top and bottom removed, etc. all work because this type of caterpillar has to curl around the base of the a stem to eat and doesn’t climb. These barriers are no use against climbing cutworms, which can hike a surprising distance up plants to chomp on leaves.

Planting for pollinators this year? If you are thinking of increasing the pollinator forage in your yard this year, give some thought to what you plant. Many plants labelled at garden centres as ‘pollinator friendly’ are anything but. ‘Nativars’ is a term for cultivars that have been selected from the original, open-pollenated, wild species. They have been bred and hybridized for improved characteristics such as bigger flowers, double blooms or different colours, as well as other traits, such as disease resistance or more compact growth. The problem is that pollinators evolved with the wild versions and don’t necessarily recognize strange colours or shapes. Nativars often produce less nectar (or none), while mutations such as double flowers prevent insects from reaching the nectar. In some cases, plants have been altered so much that they no longer provide food for pollinators: e.g., small flowered ornamental sunflowers that don’t produce pollen.

Research comparing attractiveness of wild-type flowers with nativars of the same species found that most highly selected varieties were less attractive to pollinators. For example, wild purple coneflower (Echinacea purpurea), which has purple, daisy-like flowers, is much more attractive to bees than the nativars ‘White Swan’ and various hybrids in unusual colours. Much more remains to be learned about this, but it is a compelling reason to grow the least manipulated flowers. Unlike hybrids, wild-type flowers are available as seeds. Not only does that make them cheap to grow, but by sowing your own plants you can be sure they have not been treated with neonicotinoid insecticides. These chemicals are commonly used in the horticulture trade and are known to harm bees because the chemical ends up in the pollen and nectar. The chemicals can last a season in the plant! Avoid ‘neonics’ by growing your flowers from seed or by buying them from organic growers or other sources that you can be sure have not treated their plants.

April 5, 2018 1:14 PM

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