
Cool season crops. Photo from hortupdate.unl.edu
While some gardeners are ready for the gardening season to be over, others are raring up for another round. If you are one who isn’t quite ready to throw in the trowel, now is the ideal time to start thinking about that fall vegetable garden.
Late plantings of vegetables are worth a try for many reasons. Many early planted, cool season vegetables started to fade or end production when the heat of the summer set in. Now with cooler temperatures on the horizon, it is a great time to give many of them another try. The cooler fall temperatures allow spinach and lettuce that often begin to bolt, when summer temperatures get too hot, a second chance at production. In the fall, they can be planted and allowed to mature during the shorter, cooler days. Some vegetables actually taste better if they are allowed to go through a light freeze. Crops like kale, broccoli, and Brussel sprouts are examples of vegetables that will have a sweeter milder flavor in the cooler, fall temperatures.
Not really sure what to grow? It all comes down to available space, grower preference, the intended use of the crop, and how much time we have left in the growing season. Some heat loving crops like tomatoes, peppers, and eggplant will continue to produce until frost. Other vegetables like summer squash, snap beans, and cucumbers will often begin to slow production as the summer progresses. Cool season vegetables that were planted early in the spring, like turnips, peas, radishes, and spinach faded early into summer. By planting another round of vegetables mid-summer, you can extend the production into the fall of the year. Semi-hardy vegetables like beets, potatoes, lettuce, radish, spinach, and Swiss chard are able to tolerate a light frost between 30-32 degrees Fahrenheit. Hardy vegetables like cabbage, broccoli, Brussels sprouts, carrots, turnips, and kale can stand several frosts and will continue to grow until they are killed by a hard freeze, when temperatures drop close to 20 degrees.
A little math is involved in order to figure out how much time you have left to plant a crop this fall. To estimate when or if you can still plant a vegetable for a fall crop you need to read the days until harvest. To that days till harvest amount, add the average harvest period, then add two weeks for a ‘Fall Factor’ to give yourself ample time to have the crop reach maturity and to produce a yield in the fall. The ‘Fall Factor’ takes into account the cooler temperatures that result in the slower growth of the vegetables. Once you have the magical number, get out your calendar and start counting backward from our average frost date of October 10th. Remember this date is an average and frost could come before or after that date. If we wanted to plant a radish, most are ready from seed to harvest in about 30 days. Add 14 days to that and you have 44 days from when you want to have the radish planted so it can reach maturity and be harvested prior to frost.
Just because we have a frost, doesn’t mean that the vegetable crop is toast. Normally our first fall frost is followed by 2-3 weeks of warm weather. Tender plants can continue to produce with just a little help to make it through the frost. Covering tender plants with light blankets, sheets, buckets, or newspapers can help to keep the frost off of the plant’s tender leaves and also allow the warmth of the ground to keep the plants from freezing.
Don’t throw in the trowel just yet on this vegetable gardening season. There is still some time to harvest one more crop from the garden yet this fall.
Elizabeth Killinger is the Horticulture Extension Educator with Nebraska Extension in Hall County. For more information contact Elizabeth at elizabeth.killinger@unl.edu, her blog at https://huskerhort.com/, or HuskerHort on Facebook and Twitter.