Winter Planting and Garden Editing

Many vegetables for harvest over the winter and early next spring should be planted at this time of year. So take advantage of the somewhat cooler weather forecast for the next few days to sow seeds of beets, chard and leaf beet, rutabaga, radicchio, kohlrabi and the small, quick growing, cabbage varieties (e.g., ‘Caraflex F1’, ‘Early Jersey Wakefield’, ‘Greyhound’). These should be sown immediately to have enough time to grow to a good size by the end of October. Most varieties of chard survive well outdoors through most winters, but they don’t all make it if there is exceptionally cold weather. That’s why at this time of year I include a couple of the hardier chards in my plantings: ‘Lucullus’ (wide stems, light green savoyed leaves) and ‘Leaf Beet’ (narrow stems, dark green, smoother leaf). The latter may also be called ‘Perpetual Spinach’ or ‘Bietina’ by different seed sources.

5 Varieties of Chard

From now to early August you can sow kale, collards, daikon & other winter radishes, broccoli raab and the many hardy leafy greens (mizuna/namenia, leaf mustard, leaf radish, mustard spinach/Komatsuna, arugula) and Chinese cabbage (Joi choi, bok choy, Napa cabbage, etc.). You might want to review my July 11 message last year for more details on winter crop planting and here is my planting chart showing when to sow winter crops.

You can also buy started plants for many of the above vegetables (some local sources for starts are listed below). It is too late to start the larger overwintering vegetables from seed, but you can get a successful crop by planting starts. Look for purple sprouting broccoli (winter varieties), winter cauliflower (the only varieties you will see locally are ‘Galleon’ and ‘Purple Cape’) and cabbages (most are hardy enough for winter in this region, but look for those that take less than 100 days to harvest so they have time to produce a good head).

Purple Kohlrabi

When buying transplants check varieties before you buy. I complain about this every year, but wholesale suppliers of vegetable starts to retail garden centres, grocery stores, big box stores, etc. still supply summer varieties of some crops and those fail when grown for winter. Whereas any varieties of kale, chard, spinach should do fine for winter, it is essential to make sure you are buying winter varieties of broccoli and cauliflower and that lettuce is a frost-hardy variety (most are not). To get the right stuff or for organically grown plants, it pays to buy winter starts from local suppliers that grow their own transplants. Here are a few sources I know of around the region:

Time to ‘edit’ the garden: Make room for winter crops by having a good look at what is growing in the garden right now. Are there plants past their prime or surplus to requirements? Did you plant too much zucchini, again? (You can always take out a few plant if they are getting away from you). After this hot weather, lettuce may be turning bitter and sending up a flower stalk, radishes may be splitting or too hot to enjoy. Early peas are drying up and can be cut down. You might want to take out plants that got started too late or perhaps were set back too much by pests and now don’t have time to mature. Don’t feel bad about editing these crops out of the garden—you can fill the gaps immediately with winter crops and you can always use the pulled plants as mulch.

Whether you need to add nutrients before planting again depends on how well the preceding crop grew. Established gardens with fertility built up over the years from compost, mulch and organic fertilizers probably won’t need more amendments in midseason. Soil where peas have been growing won’t either if you cut off the vines and leave the pea roots in the soil to provide nitrogen to the next crop. Soil in new gardens, however, is often low on nitrogen for the first couple of years. To beef up the nitrogen supply for the new crop, fork in blood meal, alfalfa meal, fish meal or fish/wood waste composts that are higher in nitrogen than most (e.g., SeaSoil, Earthbank, Oly Mountain brands).

And don’t forget to shade seedbeds until the seeds germinate and deploy shade cloth or other covers that let in some light for small seedlings in hot weather. Some seeds, such as carrots, lettuce and corn salad won’t germinate if the soil is too warm and you get a much better stand of seedlings if you shade the soil during the germination period. Other seeds do sprout at high temperatures, but can fry in the midday sun before they have a chance to get a root down into cooler soil. I lay covers over all of my seedbed at this time of year, both to cool the soil and keep it evenly moist without frequent sprinkling. Lift the cover as soon as the first sprouts appear, which might only take 3 days for cabbage family plants. Anything opaque works to shade the soil: sheets of newspaper, burlap, old towels or sheets, opaque white plastic (such as the bags from commercial compost), as well as shade cloth.

July 18, 2018 8:52 AM