Fall Garden Tips

Now that temperatures are dropping and the leaves are changing colors, you may think it’s time to put away your gardening tools for the year.

Not so! Here are ways to keep your garden productive right into the fall…and prepare for when springtime arrives again.

Care for Cold-Weather Vegetables

Some vegetables are just coming into their own once winds turn chilly.

Plants that can withstand light frost or air temperatures from 28° to 32° are consideredsemi-hardy. They include:

• Beet, carrot and parsnip (the tops will die back, but the roots will be OK)
• Cauliflower
• Celery
• Chard
• Chinese (napa) cabbage
• Endive
• Lettuce (short cold snaps)
• Parsley
• Pea
• Radicchio

Hardy vegetables can withstand heavy frost or air temperatures below 28°. This group includes:

• Arugula
• Broccoli
• Brussels sprouts
• Cabbage
• Garlic (plant next year’s crop after temps drop significantly but before the ground freezes) 
• Kale
• Leeks
• Mustard
• Radish
• Spinach
• Sweet onion (Walla Walla)
• Turnip

In fact, “snow acts as insulating mulch and warms the soil for these tough plants,” says greenhouse operator Robin Sweetser in The Old Farmer’s Almanac.

What’s more, you can get a couple of extra weeks from such tender veggies as beans and cucumbers by covering them “with high or low tunnels made from metal hoops and clear plastic,” says Sweetser.

Check here for average frost dates in your area. (USDA hardiness zones, which will provide your area’s average minimum temperatures, can be found here.)

Clean Up Garden Beds (and Create New Ones)

Once you’ve attended to your cold-weather vegetables, it’s time to button up your remaining beds.

Start by removing any leftover plant material, since “plants left in the ground over the winter may increase insect and disease problems next year,” according to Jessica Strickland of the North Carolina Cooperative Extension. One exception suggested by Sweetser: Remove the above-ground parts of your bean and pea plants, but leave “their nitrogen-fixing roots in the soil to feed next year’s crops.”

Your cleanup should include a final weeding; if your soil is dry, water it a few hours beforehand to make the job easier. “Just one weed left to mature can produce hundreds, if not thousands, of seeds that will grow into weeds to plague you next year,” notes Sweetser.

You can boost the productivity of next year’s garden by covering the soil with three to six inches of mulch or compost. Or you can plant cover crops such as crimson clover, hairy vetch, oats or winter rye or wheat; “this will help prevent erosion and add organic matter to the soil when you turn it under in the spring,” says Strickland.

As you work through the beds, make note of what you planted where so that you can rotate crops next spring.

“It is never good to grow plants in the same family in the same place year after year,” explains Sweetser. “Not only does it allow pests and diseases specific to that family to become entrenched, it also depletes the soil of the same nutrients each year.” (You can learn about the different vegetable families here.)

Strickland suggests also noting “any particular varieties of vegetables planted this year that you liked or performed well, as well as ones that did not.”

Want to start a new bed?

Sweetser suggests mowing the area as low as your mower will go; cover with a thick layer of newspapers, then with compost and finally with chopped leaves. “In the spring you’ll have a lovely new planting bed full of earthworms,” she says.

Test and Amend Your Soil

Before mulching or cover-cropping your beds, it’s a good idea to test your soil’s nutrient levels and add amendments as needed.

Your local coop can do the testing. To provide a sample, Sweetser suggests “mixing scoops of soil from several beds located around the garden instead of from just one spot.”

Test results may show that your soil is deficient in certain nutrients. Limestone can raise the pH of overly acidic soil; other organic amendments include:

• Animal-based fertilizers, such as blood or bone meal
• Compost
• Greensand, a source of potassium
• Manure, including that taken from chickens, cows and horses
• Marine-based fertilizers, such as fish meal or seaweed extract

You can make compost yourself using various kinds of plant material except that which is diseased or infested with bugs, which should be discarded; learn more about composting here.

Other Ways to Prepare the Garden for Winter

Inspect permanent structures such as sheds, posts and greenhouses; clean, repair and paint or apply preservative as needed. Clean all garden stakes and supports as well as tools and bird feeders, nesting boxes and baths. If your garden has a water feature, winterize that, too.

Bring in any houseplants that may have been luxuriating in summer’s warmth outside. Trim them and check for pests first.

If you have fruit trees, you should take steps to avoid damage from overwintering rodents. Sweetser suggests mowing around the trees “to discourage mice or voles from nesting, then install rodent guards made of fine mesh hardware cloth around the base of the trees to keep these pests from eating the bark.”

Fall is also a good time to plant trees and shrubs, which should be watered until first frost; conifers are especially helpful for birds, who will take refuge in them during the worst of winter weather. You should also leave a pile or two of leaves in out-of-the-way places to shelter other types of wildlife.

Now is the time to plant bulbs such as crocuses, daffodils, hyacinths, snowdrops and tulips. Ask your local nursery if you’re not sure whether bulbs you’ve previously planted will survive winter in the ground.

Herbaceous perennials, such as peonies and hydrangeas, will die back. When they do, Strickland suggests protecting the roots by applying two to three inches of mulch.