The nights are cooler. The days are shorter. Vegetables in the garden are looking peaked, and summer flowers are turning brown.
It’s prime time for some planting.
“A typical consumer looks at it as, ‘Oh, winter is coming, let’s give up gardening.’ That’s not necessarily so,” said Daniel Struve, an Ohio State horticulturalist emeritus. In fact, he recommends fall for planting many trees, shrubs, grass and flower bulbs and even fall flowers for some late color.
Sean Barnes, a horticulturist at Ohio State’s Chadwick Arboretum & Learning Gardens, agrees — noting that trees and shrubs benefit from a chance to get their roots established before the stress of a hot, dry summer.
They shared their tips for making the most of fall planting.
Are you planting trees and shrubs?
Warm fall soils promote root growth. “They really are active; you just can’t see it,” Struve said.
There are exceptions.
Some trees are better planted in the spring if they’ve lost part of their root system, such as when they are dug up and transplanted. These include oak and hickory trees, as well as trees with fleshy roots, such as magnolia and sweetgum. If you buy these trees in containers and they don’t need much root pruning, you can plant them in the fall.
- Dig a hole that’s about 2 to 3 inches wider than the root ball. You want room for fill dirt, but a small enough hole that the plant will be stable.
- Examine the roots. If they are “circling,” or matted up at the edge of the container the plant came in, you may need to cut off the bottom half inch to inch, tease out the roots on the side, or score a few cuts vertically down the roots about an inch deep. Failure to deal with the issue can lead to a stunted or unstable plant.
- Use the original soil as much as you can to fill in around the roots, and break it up well.
- Water the new plant, especially the first couple of weeks. Put a garden hose at the base and turn it on at a trickle that will soak into the ground, and run it for about 15-20 minutes a day. An alternative is to buy “gator bags,” designed to wrap around the tree and hold gallons of water that slowly release into the soil.
- Mulch around the base, leaving about 2 inches of space around the trunk so the mulch won’t promote rot.
- Consider staking the tree to keep it stable until spring when the roots are established. It keeps newly planted trees from blowing over and is meant to be temporary — just the first or second season at most. If it’s a large tree, attach cables to stakes in the ground. Otherwise, strong rope will do the trick.
- Leave burlap on the roots of your trees and shrubs. If you can’t get it all off, at least take off the top part to allow water to penetrate into the root ball. You especially want to avoid leaving any strings tied around the trunk. This will girdle the tree and kill it. “I’ve seen some crazy situations where the trunk is actually grown over the string,” Barnes said.
- Fertilize. It’s not necessary the first year.
- Tamp the soil down too tightly around the roots. Lightly tamp it with your hands, or, if you have a hard clay soil, step on it gently. Gravity and water can then settle soil down around the roots.
Get your grass back into shape
Fall is a great time to reseed grass. Bluegrass and fescues thrive in the cool nights and warm days, get roots established and have fewer weeds to compete with. They’re hardy enough to survive the winter and be ready to take off in the spring.
Watch the timing and seed early enough. A good target is no later than two weeks before the first frost in your region, Barnes said. (Look them up in The Old Farmer’s Almanac.)
Struve recommends giving the grass enough time to grow a couple inches before the first frost. The grass needs to get roots established or the freeze-thaw cycle can push it out of the soil.
Think spring flowers now
For many species of bulbs, fall planting isn’t optional, it’s essential. That’s because a dormant cycle is built in for many types of flower bulbs. They need a long period of cold weather before they break out of that dormancy.
Species you need to plant in the fall include daffodils and other kinds of narcissus, as well as tulips, crocuses and hyacinths. Exceptions are tropical bulbs such as amaryllis and gladiolus that should be planted in the spring.
“A typical consumer looks at it as, ‘Oh, winter is coming, let’s give up gardening.’ That’s not necessarily so.”
Check your growing zone before you buy bulbs. If you try to grow tulips in the deep South, for example, you may have to put them in the fridge all winter to mimic the cold cycle further north.
Already have bulbs and thinking of relocating them? Now’s the time, Barnes advised. You need to find them before they go dormant: Good clues that they’re OK to move include moist, green leaves and good roots.
“Find the bulb, and move it before the ground freezes. Be sure to leave the foliage on it to dieback naturally so that the energy gets stored in the bulb,” Barnes said.
Tropical or spring-planted bulbs should be dug up and overwintered in northern regions. You can replant them in the spring.
Find immediate gratification with fall flowers
Not all fall planting is for next year or next decade. You can plant mums before Labor Day to get a long flower show through September and October, Barnes said, as well as ornamental kale and cabbage that will bring color to your yard past the first frost.
Other flowers can be planted in the fall with a mind for spring. “Bounceback pansies” are bred to take harsh temperatures. They sprout, survive the snow and start to rejuvenate in the spring.
Other flowers to plant in fall for a spring head start include cornflower, snapdragon, calendula, larkspur and other cool season annuals.