It might seem a little crazy to talk of the fall garden already, while temperatures are still soaring high into the 90s on a regular basis. But I promise that it really is already time to get your ducks in a row for what can be the best gardening season of the year. Here’s how to go about planning your fall garden:
1. Identify your average first frost date.
Here in Laurens County, South Carolina, our average first frost date is around October 25th, but I usually round that off to about November 1st. Your average first frost date will vary, whether you live in other parts of the Upstate or in another state entirely.
To find your average first frost date, visit the National Climatic Data Center website and select your state from “Select a State (PDF)” box.
You’ll be redirected to a PDF containing a whole lot of data for different areas of your state. Scroll through the PDF until you find the name of the town you live in or, if it’s not listed, choose the town that’s closest to your home. For average first frost dates in the fall, you’ll want to look at the second set of three columns. These columns are arranged by the probability of a frost on the dates listed.
It’s important to note that what this means is that the first frost of the fall could occur on any date after the one listed in the “10” column and almost certainly will have occurred by the date in the “90” column. But the average first frost date–the mean date–for your area is listed in the second column with the heading “50”. (See highlighted area on the screenshot above.) This date is not hard and fast–remember, it is statistically possible for your first frost to occur on days both earlier and later–but it can serve as your rule of thumb for fall planting.
2. Decide which fall crops you would like to grow.
This is the fun part. Here in the South, fall is our prime time for cool-weather brassicas–kale, broccoli, cabbage, collards, and more–along with a whole range of delicious root vegetables like rutabagas and turnips that just don’t do as well or taste as good when grown in the summer heat. Growing a fall garden is a fresh start with veggies we haven’t seen in their prime for months.
Remember too that many fall greens and roots literally taste better than their springtime counterparts. At the onset of cold weather, beginning with the first light frosts, many fall greens like kale, spinach, and collards increase the amount of sugars stored in their cells in order to mitigate frost damage. These concentrated sugars act as a sort of anti-freeze within the cells. Root vegetables like carrots and parsnips grow sweeter because repeated frosts prompt the plants to convert stored starches to sugars below soil level.
If you’re just getting started with fall gardening, here are some typical fall crops that are suitable for many areas of the country: beets, broccoli, brussels sprouts, cabbage, carrots, cauliflower, cilantro, collards, daikon radishes, green onions, kale, kohlrabi, leeks, lettuce, mustard greens, parsley, parsnips, radishes, rutabagas, spinach, Swiss chard, and turnips.
3. Count backwards from your average first frost date to find out when to plant.
Now that you’ve got your list of fall crops, it’s time to figure out when to set out transplants or direct sow your veggies. I’ve put together a chart below to make it a little bit easier! The numbers on this chart came from taking each crop’s average days to maturity, adding three weeks (21 days) to the lower and upper range numbers, and then converting the number back to approximate weeks. The reason we add three weeks to the days to maturity is because as we get deeper into fall, the number of hours of daylight decreases rapidly. This decrease slows the growth of your crops just as much, if not more, than decreasing temperatures, so it’s important to take it into account.
Advanced gardeners/seed starters: If you’re planning on growing out your own starts, add 4-6 weeks (4 weeks if you’re an experienced seed starter with a solid setup, 6 if you’re a beginner and bootstrapping it) on top of the weeks listed below to arrive at your seed-starting date. Now you see why we need to start thinking about fall crops around the first of July!
As we head into late summer, stay tuned for more blog posts about getting the most out of your fall garden. In the meantime, what’s the number one fall veggie you’re most looking forward to growing this year?