Winter Planting is Here, Heat Again and Late Blight

I still feel like we are caught somewhere in endless spring, but believe it or not, some important planting windows for winter harvests are upon us.

Winter broccoli and winter cauliflower: Sow seeds from now until the end of June, either directly in the garden or in seed flats or pots. Given the rampaging slugs, pillbugs, birds and root rot diseases still plaguing us during all this wet weather, I have opted to sow mine in seedling trays and will keep them in the kitchen until they germinate (no need for bottom heat at this point). After that I will do the dance—outdoors during the day and safe and sound indoors at night, until they are big enough to plant out. If you sow directly in the garden, do sow lots of extra seeds to make sure you have enough surviving plants. These are crops that are going to occupy the garden for the rest of the season, but don’t produce heads until they have been through the chill of winter. They can be interplanted with other crops, such as lettuce or cucumbers, to make the most of the space—as long as they are not so crowded that they suffer setbacks.

Galleon Cauliflower

To repeat my caveat on broccoli varieties: there are now purple sprouting summer varieties on the market (Purple Summer; Santee), which are not the same as winter purple sprouting broccoli (though they might be hardy enough to overwinter in some places—did anyone have one of these summer PSBs overwinter last year?). The winter varieties of PSB include: Red Spear (best all-around yields, available from West Coast Seeds), you might be able to find Early Rudolph (very early, but not as productive) or Cardinal Late (larger, later heads); Territorial Seeds also lists several others that might be worth trying. Winter cauliflowers readily available in BC are Galleon (West Coast Seeds) and Purple Cape (Salt Spring Seeds). For US gardeners, Osborne Seeds in Oregon lists the hybrid Aldernay; Territorial Seeds lists an overwintering cauliflower blend. You can also seed winter cabbage this month too, as long as you get varieties listed as less than 90 days to harvest. For the longer season cabbages look for started plants. For Salt Springers: Chorus Frog farm stand on Rainbow Road currently has those long-season cabbage starts and is aiming to have seedlings of winter PSB & cauliflower on the stand around mid-July.

Of course, long time readers will remember that Carrot Day (July 1) is fast approaching (July 4 for you US readers….). While you can sow carrots any time before that, early July is the last chance for sowing carrots to make sure they have time to mature to full size before the end of the growing season. Early to mid-July is also good timing to sow beets, rutabagas, radicchio, kohlrabi and lots more Swiss chard for winter. Your spring sown chard will be fine through the winter, but you probably want to add more plants to account for the fact that plants won’t grow new leaves during winter. I usually plant another patch of chard about 4 times larger than what I planted for summer eating. By the way, the finer stemmed Leaf Beet (AKA Perpetual Spinach, Bietina) and broad stemmed Lucullus chard were the hardiest chards in my garden last winter, with every plant surviving (only one plant each of Bright Lights and Fordhook survived). Although the latter are rarely killed by cold, I do plant the hardier chards, just in case… see my web site for a planting chart pdf that you can print out, showing when to sow what for winter harvests.

Heat wave again? Just a reminder that leaves of all garden plants are extremely soft and succulent after all this prolonged cool, wet weather. These leaves will burn in bright, hot sun if it the higher temperatures materialize as forecast later this week so be sure to shade plants during the hottest days. Until leaves get used to bright sun, they are easily fried. And new seedlings will need special attention to their welfare through heat waves….see notes from my previous story for more details.

Beware late blight on tomatoes: Not to be too doomy, but so far we have had prime [wet!] weather for late blight to strike tomatoes. We got away with two long, dry growing seasons in the last 2 years and I think some gardeners have forgotten about the risk of late blight. The fungus-like organism that causes the disease infects wet leaves, but can’t infect dry leaves; it usually shows up later in the season, but I have seen it demolish tomatoes in June. The only defense we have is to keep leaves dry (resistant varieties developed for eastern growers so far don’t work well here—there are many strains of this organism). Uncovered tomatoes are at risk in rainy weather and once infected, there is nothing you can do about it. Plants progress to total collapse very quickly.

Tomato Tunnel Prevents Late Blight

Making sure leaves don’t get wet is the most effective way to avoid late blight: Grow plants in pots under the overhang of a roof or in a greenhouse or protect plants in gardens from rain with a clear plastic roof of some kind. A very successful design is a high plastic tunnel, with the frame tall enough to allow plants to reach full height and still have lots of space around them. The tunnel should be open all around the sides and at both ends. Good ventilation in tunnels is essential to prevent condensation from wetting leaves. Also make sure you don’t wet leaves when you water plants. Micro-irrigation systems that spray water onto plants are risky for tomatoes (and some other vegetables) because regularly wetting leaves gives destructive leaf diseases ideal conditions to develop.

About Linda A. Gilkeson, Ph.D.

Salt-Spring---Linda-GilkesonLinda earned a Ph.D. in Entomology from McGill University in 1986, then moved to British Columbia to work for Applied Bio-Nomics Ltd., a company that produces biological controls. From 1991 to 2002 she worked for the provincial government, promoting programs to reduce and eliminate pesticide use. She was head of the provincial State of Environment Reporting Unit for the next six years, then the Executive Director of the Salt Spring Island Conservancy until the end of 2011. Linda now devotes her time to writing, teaching and consulting.

Linda has co-authored pest management training manuals for the government and organic gardening books for Rodale Press. She has self-published two books: Year Around Harvest: Winter Gardening on the Coast and West Coast Gardening: Natural Insect, Weed and Disease Control. Her recent book, Backyard Bounty: The Complete Guide to year-Round Organic Gardening in the Pacific Northwest, has become a BC best seller.

As a private consultant, Linda is a regular instructor in the Master Gardener programs in BC and is busy year around giving workshops on pest management and organic gardening.

Linda has served as President of the Entomological Society of Canada, the Professional Pest Management Association of BC, the Entomological Society of BC and the Salt Spring Island Garden Club. She was awarded a Queen’s Jubilee medal in 2003 and an outstanding achievement award from the Professional Pest Management Association of BC in 2005.

Follow Linda's work at­­­­­­­­­­­­­­­

June 21, 2017 8:59 AM

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