The fall season will be here soon, so now is the time to start planting fall vegetables, such as broccoli, collards, kale, cabbage, turnips, onions and others. Late August, September and October are the best time to plant them. The weather will be starting to cool down but the temperatures are still warm enough for the plants to become established.
Begin preparing for the plantings by removing and disposing of the dying summer vegetables and rake any debris from the surface of the ground. Insects and diseases can over winter in this debris. Have your soil tested through Gwinnett County Extension and apply fertilizer according to the recommendations.
In lieu of a soil test, apply one to two pounds per 100 square feet of an all-purpose fertilizer like a 10-10-10, 6-12-12, 5-10-15, or one with a similar ratio and incorporate it into the soil. Apply a one to two-inch layer of organic mulch, such as pine bark or pine straw, to control weeds and keep the soil evenly moist.
Choosing what to grow depends upon your own preferences. Cabbage comes in green, red and savory (wrinkled) varieties. Harvest the cabbage heads by cutting just below them with a sharp knife. If they become overly mature, the cabbage heads will crack, especially if the soil has been dry and suddenly becomes wet.
Broccoli requires minimal maintenance. Harvest the heads when they are small but before the buds begin flowering. Leave roughly six inches of the stem attached. Let the side lateral shoots grow to develop more flower heads. Leafy greens, such as collards, kale, and mustard greens, are quite tolerant of the cold. They can be harvested when they are a small size or when they have matured. As the weather begins to warm in the spring, these plants will begin to flower and go to seed. This is the time they should be removed.
Several root crops thrive in the cold weather. Turnips are grown for both their roots and the leafy greens. Harvest the root portion of the plant when it reaches a width of two to three inches. If they grow any larger, they will become pithy and inedible. Bulb-type onions and green bunching onions are planted in the fall and will be ready for harvest in the spring. Radishes mature within 30 days and are easy to grow. Make successive plantings of short rows every 10 to 14 days to get a continual harvest. Radishes can be sown in spaces between slow-maturing vegetables like cabbage or broccoli. Other root crops that thrive in cooler weather include beets, rutabagas and carrots.
Several caterpillar pests, such as the cabbage looper, can cause problems for the vegetables. Insecticides are available containing bacteria that specifically target the caterpillars. They are sold by the trade names such as Dipel or Thuricide. Aphids are frequently a problem. Use insecticidal soaps or in some cases just wash them off with a hose.
Yes, even in cold weather you can harvest vegetables from your garden. With a little planning and preparation, fall vegetable gardening can be a productive and a rewarding endeavor.
Timothy Daly is an Agricultural and Natural Resource Agent with Gwinnett County Extension. He can be contacted at 678-377-4010 or via email at firstname.lastname@example.org