The average date of the first killing frost locally is the most important thing to know when it comes to fall vegetable gardening.
To determine when to start planting, find out the number of days to maturity for the vegetable. Next, count back the number of days from the first average frost date. Some gardeners add a week or so to allow for a few extra days to harvest the produce once it matures. Maturity information is listed on seed packets and some plant labels.
Most everything planted in spring will grow in a fall garden. These are cool season plants, meaning they will tolerate a light frost, thrive in short daylight hours and perform best with mild temperatures. Some vegetables even taste better when nipped by a light frost.
4 Best Autumn Veggies:
Broccoli.
Broccoli seedlings should be planted 10 weeks before the first frost date. This means planting them during the last hot summer days, so it's important to mulch around them to help keep the ground cool and moist. Feed the plants 3 weeks after transplanting into the garden. Use a low nitrogen fertilizer. 70 days to maturity.
Brussels Sprouts.
Brussels sprouts are ideal for fall gardens because they really taste best when allowed to mature in cool weather. Set the plants out in mid-summer; it will take about 3 months before the sprouts appear. They are ready for harvest when they are firm and green. 90 days to maturity.
Cabbage.
Plant seedlings 6 to 8 weeks before the first frost. If the heat of summer is still intense when it's time to plant in your area, give the young plants protection from sun. Cabbages are heavy feeders that require fertile soil rich in organic matter and consistent moisture. 70 days to maturity.
Cauliflower.
Plant seedlings 6 to 8 weeks before the first frost. Cauliflower can be tricky to grow. Rich soil and consistent watering are key. Fluctuations in temperature, moisture and nutrients can cause the plant to "button" or produce small, undersized heads. Blanch the heads by tying the outer leaves together over the heads when they are about 2 to 3 inches across. This keeps them from turning green and becoming bitter. 60 days to maturity.