Sow What Now in September
September arrives with an abundant harvest and mild weather. But, as the month proceeds, it also inevitably signals the start of fall with its cooler, windier, and shorter days. In the garden, the transition of the seasons means a shift in nearly everything – the pace and rhythm of work, the chore list, the outlook for the future. Expect less weeding this month and more soil care, less plant care and more harvest preservation in the kitchen, less growing for near-future harvests and more seed sowing and planning for the next growing season.
Sow Now What: Although the first frost (due to hit the Hudson Valley some time next month) marks the grand finale for the majority of plants and thus, greatly limits sowing opportunities at this time of year, there is still an array of beautiful and delicious crops brave enough to march into the cold future.
September marks the beginning of flower bulb planting season, so they can settle in for a long winter and be ready to emerge colorfully next spring. Bulbs, unlike seeds, like to be placed deep in the ground. Dig a hole that is two or three times deeper than the bulb. Plant it right side up: the round end of the “tear-drop” should be on the bottom, pointy end facing up. Cover back up with soil and water in well to help the bulb establish roots. Flowering bulbs look best when grown together like a loose bouquet, so consider scattering them about (still mostly following the suggested spacing) instead of planting in straight rows. Keep the planted area weeded to eliminate the competition for water and nutrients. If you find that some bulbs get “un-planted” by hungry critters, consider protecting your bulb bed by laying down a sheet of chicken wire over it, removing when the plants sprout in the spring. Aim to plant fall bulbs anytime before the ground freezes.
September also marks the opening of the garlic planting season. Although it's okay to wait until October or even November to get seed garlic in the ground, it’s good to plant this stinky treasure early to give your cloves time to set some roots before the hard cold sets in. Keep in mind that garlic needs a bed with lots of organic matter as well as mulch. For more detailed planting instructions, have a look at this garlic planting guide.
Spinach and Mache aren’t afraid of the cold and can be there to greet very early spring in the garden. Sow them now to start preparing your first salad of 2021. Prepare beds for them by weeding thoroughly and aerating the soil, either by raking or, if your soil is compacted, by lightly tilling. Sow them in rows on the surface and water well but gently, so as not to displace the seeds. Keep in mind that mache is a prolific self-seeder; be sure to plant it in an area where you’d like to see mache come back season after season. To get to know these hardy greens closer, read our plant personalities on Mache and Spinach.
Other greens, such as Arugula, Asian Greens, Kale, and Mustards can be sown this week for fall harvests of baby leaves. Covering them with row covers is an effective way of extending the season after the temperatures drop. Row covers will protect your greens from the frost and will enable them to grow faster. For more about which greens are great to grow this month and how, take a look here.
As the growing season winds down, leaving empty rows and gaps throughout your growing space, it’s a great time to prioritize soil care. One of the best ways to help your soil rejuvenate itself through the winter and enter spring with new strength and vigor is to plant cover crops. Cover crops restore nutrients back into the ground, prevent erosion, and keep down weeds, to name just a few benefits. They are easy to sow: simply scatter evenly across the bed surface, rake in lightly, and water in well. To learn more about the role of cover crops, take a look at our post on Fall Cover Crops for Home Gardens.
Row Covers and Cold Frames: In the Hudson Valley, we are about a month and a half away from our expected first frost date. Although many crops are tough enough to withstand a few light frosts (like Brassicas and some greens), many (like Solanaceous crops) are too tender and shrivel up after just one. Row covers increase the soil temperature by a few degrees by trapping daytime heat under the cover, marking the difference between death and continued harvests for some plants. For hardier crops, the added warmth speeds up the ripening process, meaning a few extra weeks of harvests despite obstacles like cooler temperatures and shorter days, which slow down growth. You don’t have to wait till the first frost warning to begin using row covers – start by protecting the most tender crops when temperatures cool down toward the end of September. To learn more about row cover use, take a look at our articles on row covers.
A cold frame is another great tool for extending fall harvests and starting spring planting extra early. To learn all about the advantages of cold frames and how to build one yourself, take a look at Doug’s Quick and Easy Cold-Frame Tutorial.
Soil Care: the end of the growing season is the perfect time to say thank you to the soil that has worked so hard to keep your crops happy and healthy. Before fall plantings, consider an additional application of one inch of compost as well as a repeat of your regular amendment regimen to keep your soil as balanced and strong as it keeps your plants.