The summer harvest is in full swing. Tomatoes, eggplant, peppers, corn, squash, and melons are ripening, giving us the fresh fixings for many a delicious summer meal. But the days are getting shorter and fall is on the way. It's time to think about planting to continue the harvest as the seasons change.
Cool Season Harvest
There are lots of great choices when it comes to vegetables that do well as the weather cools in fall. These include lettuce and other hardy greens, spinach, kale, collards, leeks, cabbage, broccoli, Brussels sprouts, and kohlrabi. But in order to reap a harvest before it gets too cold, you need to begin planning and planting in mid to late summer in many areas. The longer the frost-free season in your part of the country and the milder the winters, the more extended your fall harvest can be. But even gardeners in short-season northern areas can enjoy some fall pickings if they plan ahead.
Giving your plants some protection from the cold is another way to extend the gardening season. Cold frames, fabric row covers, cloches, and low tunnels can all offer varying degrees of protection and extend the harvest well beyond that of the open garden.
When to Plant
Planting times for fall crops will depend on where in the country you garden. Gardeners in southern areas will be able to plant later and have a wider variety of crops to choose from than those who garden where frost comes at the end of September or earlier.
To figure out the best fall planting times for your garden, start with the average date of your first hard fall frost (when temperatures dip to 28 degrees), since most cool-season crops can take a light frost without harm. Then take the days to maturity for the crop you plan to grow and count back this number of days from the frost date. (If the days to maturity listed is from transplant, not seeding, add another 4 weeks to this figure.) Because plants grow more slowly in the shorter, cooler days of fall, add a ″fall factor″ of another week or two to the maturity time. Then add in the length of the expected harvest period and you've arrived at your planting date.
As an example, the days to maturity for Black Seeded Simpson lettuce is 45 days. Add a 7 day ″fall factor″ and a 14 day harvest period for a total of 66 days. If your fall frost is around November 1, you'd need to plant your seeds by August 26. If you plan to offer your plants protection you can plant 2-3 weeks later and still expect to get a good harvest.
It may be too late in the season for many gardeners to plant crops like Brussels sprouts that, while they are great for fall harvests, take a long time to mature. But it's never too soon to be planning for the next season!
Tips for Fall Crops
Plant in succession: Plant fast-maturing crops such as lettuce, arugula, mustard, mesclun, and mache in succession. Make a small planting every few weeks from midsummer on to enjoy a continued harvest through the fall.
Gamble a little: Every season is different and you never know when the really cold weather will hold off, giving you a longer harvest. If you're willing to push the envelope and make your last plantings a little later than recommended, you may be rewarded with an extra long harvest season some years.
Invest in a cold frame: This is one of the handiest tools for extending your growing season. A cold frame can give you an extra month or more of growing time in the fall (not to mention a place to give plants an early start in spring), especially if you cover it with an insulating blanket on nights when the temperature dips particularly low. There are lots of commercially made options, but it's also easy to build a cold frame yourself if you have some basic tools. An online search will provide plans.
Mulch root crops: You can extend your harvest of beets, carrots, turnips, and parsnips by mulching over them in the ground before the ground freezes hard. Place a foot deep layer of straw on top of the plants, extending out about 18 inches on either side of the row. Move the mulch aside to dig the roots as needed, then cover the plants back over. Even in northern areas, you can often continue your harvest up until early winter this way.
Question of the Month: How to Preserve Herbs
Q: What's the best way to preserve the herbs from my garden?
A: One of the easiest ways to preserve herbs such as chives, parsley, tarragon, and dill is to freeze them in ice cube trays. Chop the leaves of your favorite herbs, pack into the trays, cover with water, and freeze. Store cubes in plastic bags in the freezer and pop them into soups this winter. Drying is the traditional way to preserve many herbs. Make small bundles of herbs tied with twine and hang them upside down in a warm spot out of direct sun with good air circulation, or spread them out on a tray made of window screening. Dry plants until they are brittle and crumble easily.