Dear Helen: I just heard an听alarming radio interview with a meteorologist who predicted another long, wet, cold winter. I thought surely we were due for a mild one. What should I do to protect the leeks, winter cabbages, over-wintering cauliflower and sprouting broccoli, kale and other leafy greens from freezing weather? J.R.
Similar forecasts in the media recently will be alarming gardeners who lost even very hardy plantings like kale last winter. Most plantings can be saved by watching weather forecasts carefully from now through early spring and by having protective measures ready to employ.
If you have leaves from your own garden, or have access to some, use them to mulch around winter vegetable plants. Light, fluffy leaves, or larger ones that have been mowed over or run through a chopper, are best. Use any extras to cover the soil in emptied vegetable and flower plots.
Stake taller, top-heavy winter vegetables like Brussels sprouts and sprouting broccoli, to secure them against toppling in winter storms. Cover the tops of parsnips, carrots and beets with several inches of leaves or five cm of soil to protect the tops from turning to mush in a hard frost.
Leeks are not all equally hardy. If you still have the seed packets or the catalogue you ordered from, check the descriptions on the variety or varieties you have to find the preferred harvest time. Some are summer leeks. Others are designed for fall harvesting, and still others can be harvested through the winter into early spring. If you have grown two or more varieties, use the ones for all-winter harvesting last.
Leafy greens with soft leaves (winter lettuce, spinach, chard, radicchio) need covering in more than just a few degrees of frost. Because I鈥檝e used lightweight, floating row cover fabrics for years as insect barriers to vulnerable crops, I have a good store of听the used fabric in the garden shed. I use this material to cover leafy greens 鈥� one to three layers at a time depending on the degree of cold forecast. Old, lightweight curtaining, sheets or tarps can also be used. Remove coverings when temperatures rise above freezing.
When frosts colder than -5 C are predicted, similar temporary coverings over kale, over-wintering cabbage family vegetables and leeks will be helpful.
听
Dear Helen: My preference is to purchase all my plants at local nurseries, but sometimes I can鈥檛 find a particular variety. Have you any ideas on making such plant searches more successful?
L.P.
A time-saving first step is to phone your local garden centres to see whether they have the plant you desire in stock. Remember that plant choices are at their most plentiful in spring. If a garden centre doesn鈥檛 have the plant, ask whether they can bring it in for you.
It鈥檚 helpful, whenever possible, to get to know the buyer or buyers at your most accommodating local garden centres. They are the people who can most quickly determine whether they can get a plant for you.
If the idea is appealing, and patience is one of your virtues, consider seeking the plant you want in seed form. Some of my most treasured plants are ones I鈥檝e grown from seed 鈥� tree peonies, daphnes, clematis, Cistus (rock rose or sun rose) and more. Since growing them, some have disappeared from catalogue pages, making them personal garden 鈥渆xclusives.鈥�
Two sources for tree, shrub,听climber and perennial seeds are Chiltern Seeds (chilternseeds.co.uk) and Plant World Seeds (plant-world-seeds.com), both in England.
听
Dear Helen: A pink dogwood I听planted in the spring developed powdery mildew on the leaves and stems after the fall rains started. Would a dormant oil spray after all the leaves have fallen help? Should all the fallen leaves be cleaned up?
O.R.
Dormant oil sprays are used to smother over-wintering eggs and pupae of insect pests and for that purpose are most effectively applied in late winter, before growth buds begin swelling on trees and as the eggs and pupae are at their most (pre-hatching) vulnerable stage.
Lime sulphur sprays applied in dry, mild weather in the dormant season should help to reduce over-wintering powdery mildew fungus on the tree. Cleaning up all the fallen leves is important for the future health of the tree. When the ground under and around the tree is clear, lay a light mulch of topsoil or compost (purchased or home-made) over the area.
During the growing season watch for dead and diseased twigs. Remove them, only in dry weather, after the flowering period.