From Linda Gilkeson:
This message turned out to be one long “do” list, mirroring my own list of tasks for this month–so here it goes:
-Last chance to sow for winter salads: You can scatter corn salad seeds around under tomatoes, peppers, squash, etc. that will be finished in October. Rake back the mulch in patches and broadcast the seeds on the soil. If you water them they will come up quickly, but if you don’t they will still come up, just later. When it gets cooler and wetter you will suddenly see the soil covered with tiny seedlings. Corn salad is about the only veggie I know of that actually puts on noticeable growth during the winter.
-Try fall seeding for spring salads: Frost hardy lettuce varieties seeded this month don’t get big enough to pick this fall, but the little plants get their roots down and survive winter. They will be the first plants up and ready to harvest in early spring. I find this timing more reliable than sowing seeds outdoors in early spring (or fussing with starting early lettuce indoors).
-Check whether carrots, beets, lettuce, spinach, Chinese cabbage and other crops sown in the July and August need to be thinned and weeded for these last few weeks of good growing weather.
-Harvest winter squash and pumpkins when they are fully mature, which you can tell by checking the stem of the fruit. If the stem is as hard as wood and you can’t dent it with a fingernail, the fruit is ready to pick. BUT, if you are not certain, just leave them—they won’t get over-mature on the plants so you are better to err on the side of leaving them longer than risk picking them too early.
-Support branches of late varieties of apples and pears if they are still carrying lots of fruit. Use temporary stakes to prevent branches from breaking in wind storms (which could happen any time now).
-Pinch off new flowers on vining (indeterminate) tomatoes or cut off the tops of the plants now so that they put their energy into ripening the fruit already set on the plants. You can usually wait to the end of the month to do this for plants in unheated greenhouses.
-If you are growing sweet potatoes [AKA “yams”], harvest them this month when the weather takes a turn to prolonged cooler, wetter weather. We are still having nice warm days this week, but sweet potatoes consider 5 degrees C [40 F] temperatures as an excuse to give up the ghost so there is no point in leaving them out after nights get cool.
-By the end of September snip out the tips of Brussels sprout plants to force development of sprouts. If your plants are only a couple of feet high and have yet to show any sprouts, this is especially important, because it will ensure the plants produce at least some crop. Remember these are biennial plants and if they haven’t grown sprouts this fall, they won’t make sprouts in the spring as that is when they send up flower shoots. If you have a good crop of nicely developing sprouts all along stems of tall plants by now, pinching out the tips is optional, though I still do it to get even sprout development. Start staking up tall Br. sprouts plants for winter because they are top heavy and easily toppled by winter winds or heavy, wet coastal snow.
-After the drought this summer plants that couldn’t be irrigated sufficiently can take up water too fast when the fall rains start, causing splitting. To slow down water uptake and prevent cabbages from splitting, when heavy rain is predicted give the head a slight yank or twist. You just want to disrupt the fine root hairs temporarily, not dislodge the roots from the soil. Plums are especially prone to splitting too so be prepared to harvest late plums immediately if there is heavy rain before they are picked (they can finish ripening off the tree if you catch them before they split).
Pest and disease note:
The white dusting of spores from powdery mildew fungi is a common occurrence this time of year, especially on leaves of squash, peas, cucumber. There seems to be less of it around than usual this year, at least in my garden. Many winter squashes have matured already due to the hot summer, leaving fewer plants to be infected, but even my remaining summer squash seem to be less infected than usual. If you would like more information on powdery mildew, see my last year’s Sept. 3 message:
Every year I get questions about those small stubby little brown butterflies that look like small moths flitting around gardens in large numbers in the fall. Not to worry! Those are grass skippers, probably mostly a native species, the Woodland Skipper, though there are a few other less common species in the region.
Republished with permission from Linda Gilkeson’s Gardening Tips. See Linda’s website to sign up for her newsletter, purchase books, access free presentations and identify pests and diseases which may affect West Coast gardens.