Fall Chores: Divide Perennials

As the weather is cooling off, we’re spending a lot of time pulling in the harvest, saving seeds, and sneaking in a few last-minute fall crops. It’s also an ideal time to divide perennials. Fall’s cooler temperatures and the plants’ natural transition into winter dormancy help to put less stress on your plants.

Why Divide Perennials

One of the main reasons we divide our perennials is to help them thrive. When we divide perennials, we provide more space for the roots to grow. When they’re less crowded, they can absorb more nutrients and water.

Sometimes, we divide perennials when they get out of hand in a particular space. Vigorous plants like Rudbeckia can fill a garden bed and start leaning into pathways and other beds. Dividing them is an excellent way to manage them.

Lastly, dividing perennials means we get more plants! We can share our divisions with friends and neighbors or add them to our gardens. In ornamental gardens, repetition is often a key design element, and dividing perennials is an affordable way to achieve this look. Divisions for medicinal herbs and food crops mean you’ll have larger harvests in the future.

Chives (divide perennials)Perennials You Can Divide in Autumn

Not all perennials can be divided, and of those that can, not all of them like to be divided in autumn. Certain perennials, like the fall-blooming chrysanthemums and asters, do best when divided in early spring. These are a few of our favorites to split this season, but we recommend researching what’s best for your plants.

  • Rudbeckia (Black-eyed Susans)
  • Peonies
  • Chives
  • Salvia
  • Daylilies
  • Coreopsis
  • Yarrow
  • Feverfew
  • Butterfly Weed
  • Echinacea (Coneflowers)
  • Mint
  • Lemon Balm
  • Skullcap
  • Horseradish

It’s also important to remember that dividing your plants will look different depending on the species. Some perennials have traditional roots or fibrous clumps of roots, while others have tubers, rhizomes, or long, tough taproots. 

Tools to Divide Perennials

At a minimum, it’s best to have a sharp spade to divide perennials. Other tools that can be helpful include a garden knife, shears, trowel, a 5-gallon bucket or large nursery pot to carry plants, and a tarp to contain soil if you’re working in a pathway or lawn.

How to Divide Perennials

Use your knife or shears to prune stems and foliage about 6 inches above the ground. This helps to decrease moisture loss.

For plants with traditional or fibrous roots, dig up the plant, getting as much of the roots as you can. If it’s a large patch, you may need to dig just sections at a time, using a sharp spade to cut a section. Once your plant is out, you can divide it with a garden knife or spade. Plants with fibrous roots can be very tough to cut.

When dividing plants like horseradish with long taproots, try to dig as much as possible and include decently sized roots in each clump. For example, horseradish roots should be pencil-sized or thicker to support the plant going into winter. 

Dividing plants with rhizomes is similar. Dig them up, damaging as little of the rhizome as possible. You’ll often be able to pull the rhizomes apart by hand. 

Peonies tend to be fussier than other perennials. While they rarely need dividing, you can split large plants, though the divisions may take two to three years to bloom again. Cut peony roots into sections with at least three eyes.

How to Replant Perennials

Dig a hole 1 1/2 to 2 times its size to give your new perennial the best start. Try to replant your divisions so that the soil is at the same level as it was previously. Peony roots should only be plants about 2 inches below the surface.

Fill in around the roots with a mixture of soil and good-quality finished compost. Pat the soil around the roots gently but firmly. Water your plant deeply and keep up with consistent watering for several weeks, especially if you’re having a dry fall.

If you’re not replanting your perennials immediately, don’t let them dry out! You can keep them for a few days while you decide where to put them or transport them to a friend’s as long as they’re well watered.

Fall isn’t all about the harvest! We’re already dreaming of the summer garden to come. This fall, You can divide perennials to rejuvenate your flowers, share with friends, and get a few more plants growing in your garden. Follow this simple guide to have success dividing your perennials this season.

Stretch the Season: 7 Fall Gardening Tips

Fall can feel like a welcome respite after a busy summer season full of vegetables, flowers, and herbs. Even so, some of us can’t help but try to keep the garden bursting with life for just a little longer. Here are some simple fall gardening tasks you can do this season and in future seasons to help your garden stay gorgeous and productive a little longer each autumn.

What Can I Do Right Now?

It may be getting late in the year, but you can still do a few things to make a big difference right now. Give these fall gardening tips a shot this September.

Deadhead Your Flowers

Many flowers will continue blooming until the frost kills them, especially when they’re frequently deadheaded. Keep up with deadheading your cosmos, zinnias, marigolds, chrysanthemums, coreopsis, salvia, and other flowers to keep them blooming and looking fresh.

Sneak in a Few Last-Minute Vegetables

Depending on your location, you may still have a chance to sneak in some last-minute vegetables. Here in Virginia (zone 7), we’re still tucking in radishes, turnips, spinach, and mustards this week. We’ll soon be planting garlic, shallots, perennial onions, and bulb onions. Farther south, folks still have a long list of crops they can grow.

When determining appropriate fall planting times, we recommend that folks use the days to maturity and calculate back from your average first fall frost date. Then, add 14 days to the listed days to maturity for your variety to account for the “fall effect” of shortening days and cooler temperatures. 

Apply Mulch to Insulate the Soil

Applying mulch in the fall will help keep your soil warmer for longer. Around perennials and overwintered greens, mulch will help insulate roots through the winter. For annual root crops like beets and carrots, it can also allow you to leave them in the ground much longer. In some southern areas, leaving them in the ground to harvest them through the entire winter may even be possible.

Row Cover and Garden Beds in front of SESE Building (fall gardening)Invest in Row Cover or Coldframes

Not everyone has the space, time, or money to put up a high tunnel or greenhouse, but don’t let this stop you from adding some season extenders to your garden. Season extenders can completely change your fall gardening game!

Ordering row cover and some wire hoops is a fast way to give your plants a few degrees of protection from cold and frost. Cold frames also provide protection from winter weather, and many people can DIY these with a few cheap supplies like old windows and hay bales. 

Even after September, these are still valuable additions to the garden. We sow very late crops like bulb onions and spinach in cold frames to overwinter and get a quick start in early spring. This gives us larger onions and extra early greens.

Reduce Wind Exposure

In the fall, plants are fighting a battle against dwindling daylight and colder temperatures. Adding winds to the mix means your plants use all their energy to survive. You won’t see them grow and flourish unless you add wind protection. 

Adding windbreak netting or some sort of windbreak can help your plants thrive. You don’t need to stop all the wind; focus on reducing wind speed.

In future seasons, you can improve wind protection by planting windbreaks of trees and shrubs or building fences. 

Zinnias (fall gardening tips)Fall Gardening Tips to Implement in the Future

If you’d like to do more, there are a few steps you can take before next season that will help your fall garden be even more beautiful and productive. Here are a few things to think about.

Create a Fall Gardening Succession Plan

Great fall gardening starts well in advance! When you’re planning your garden and purchasing seeds, bulbs, and plants, make sure you think about succession planting. For vegetable patches, this means that when one crop finishes, you start a new one to ensure your beds are always full and there’s always something fresh on the table. For example, you might grow a fall pea crop after your corn comes in for the season or plant lettuce once your tomatoes are done.

In a flower garden, the focus is to have some blooming all through the season, including into autumn. Look at average bloom times for bulbs and perennials. Read seed packets for days to maturity on annual flowers. Add this information to a calendar and see how you can fill the gaps. To help extend blooms into fall, plant multiple successions of annuals. For example, continue sowing cosmos and zinnias late into the summer.

Add Larger Perennials, Shrubs, and Trees

If you’re working on an ornamental garden, one thing you can do to keep it attractive year-round is to vary the height and textures. These help add interest when little is blooming. Native trees and shrubs with berries or evergreen foliage can provide interest even into the winter and are excellent habitats for songbirds and wildlife. Shrubs like rhododendron, bayberry, and mountain laurel are good choices, as are trees like magnolia, cedar, and holly. You may also consider some wood ferns and other evergreen or semi-evergreen perennials.

Despite all the hard work that comes with a garden, it can be hard to say goodbye to the fresh food and beautiful flowers when the leaves start to drop. Whether you have a large vegetable garden, herbal medicine garden, cut flower garden, ornamental garden, or a combination, these tips will help you keep growing into autumn and winter. 

Helpful Gardeners: Support Migratory Birds

Autumn is a busy time for gardeners as we sow fall crops and finish the summer’s harvesting and preserving. It’s also a critical time for migratory birds. Many of these birds have spent their summers helping our gardens thrive. They’re the Ruby-throated Hummingbirds that pollinate our flowers, the Goldfinches that feed on weed seeds, and the Eastern Bluebirds flitting through the beds, snatching up pests. This fall, there are a few simple steps you can take to help support migratory species and ensure their population returns next season.

Common Migratory Birds in the Eastern United States

Bird migration varies over species. There are short-distance migrants that move to nearby areas with more food availability, often between low and high-elevation regions. In many places in the eastern United States, American Robins are short-distance migrants.

Medium-distance migrants will often fly south in the fall, just as far as they have to avoid extreme weather and food shortages. Often, these migrations are just a few hundred miles. The Eastern Towhee is a common medium-distance migrant. Those in the Northeast often fly to Virginia or a bit farther south in the winter. Individuals in the Southeast may not migrate at all. 

Long-distance migrants usually move to breeding grounds in the United States and Canada in the spring and return to wintering grounds in South and Central America in the fall. Ruby-throated Hummingbirds are an excellent example of this migration. Most individuals leave North America in the fall and winter from Mexico to Costa Rica or Panama. 

Here are a few of the species you may spot moving through the Eastern United States in spring and fall:

  • Chipping Sparrows
  • Eastern Bluebirds
  • Eastern Towhees
  • Evening Grosbeaks
  • Field Sparrows
  • Goldfinches
  • Hermit Thrushes
  • House Finches
  • Indigo Buntings
  • Purple Finches
  • Ruby-crowned Kinglets
  • Ruby-throated Hummingbirds
  • Scarlet Tanager
  • Song Sparrows
  • Yellow-rumped Warblers
Female Ruby-throated Hummingbird visits a Red Cypress Vine flower
Female Ruby-throated Hummingbird feeding on Red Cypress Vine flower

How Can You Help Migratory Birds?

Migratory birds are struggling. In today’s rapidly changing world, these excellent garden helpers struggle to adapt and cope with climate change, habitat loss, pesticide use, light pollution, and collisions with vehicles, buildings, and other human-made structures.

While we can’t fix all of these issues, you can take a few simple steps to lend migratory birds a helping wing.

Go Lights Out for Birds

Light pollution doesn’t just affect stargazers and moths; it’s a severe threat to migratory birds. Bright light sources often disorient these birds, which typically migrate at night. Disoriented birds may hit buildings or waste energy and become exhausted and more susceptible to predation. 

Turn off exterior and decorative lighting. For essential outdoor lighting, switch to motion sensor lights or down-shield lighting to eliminate glare and upward-pointing light.

Turn off interior lighting at night, especially in higher-story buildings. Pull curtains at night to cover windows in areas where lighting is necessary or use task lighting. 

You can also get others involved by working to start an Audubon Lights Out Chapter in a  city near you.

Make Daytime Windows Safe

Many people have heard or seen a bird hit a window. They see the reflection in the glass and perceive it as a habitat they can fly into. Use glass paint, strings, screen, or film to break up these reflections and make them easier for birds to spot. Encouraging local businesses to create window murals can save birds from this fate.

Keep Feeders and Bird Baths Clean

Bird feeders can be especially helpful for migrating species like the Riby-throated Hummingbird that need all the energy they can get for a long journey. That said, it’s essential to keep them clean and sanitary. Especially during migration, hundreds of birds may visit a single feeder, which can spread disease if not kept clean. The same goes for bird baths. Dirty bird baths can spread diseases, contain harmful algae, or become breeding grounds for disease-carrying mosquitoes. 

Hold Off on Garden Clean-Up

Birds will probably enjoy your garden and yard better if you don’t keep it perfectly tidy. Leaving standing dead plants a little longer allows resting places for migratory birds to hide and search for insects as they journey south. This also applies to standing dead trees in forested areas on larger properties.

Indigo Bunting perched on Tansy Ragwort (migratory birds)
Indigo Bunting perched on Tansy Ragwort

Plan a Migratory Bird-Friendly Garden

As you plan for next year, think about birds as you plan your garden. Flowers like sunflowers, Black-eyed Susans, and echinacea provide great food for pollinators and seed-eating birds. Species like mulberries, chokecherries, elderberries, and serviceberries are also great options for feeding the birds without a feeder. Whenever you can, native plants are an excellent choice.

Varying the height and texture of plants in your garden can also make it more attractive to many small bird species, which will find places to hide and nest in dense shrubs and places to perch on taller trees and plants. 

Support Bird-Friendly Legislation

Legislators have the power to influence changes on a larger scale. Encourage local or state legislators to support legislation like the Federal Safe Buildings Act or other legislation focusing on sound farming practices. These issues can make a huge difference in protecting migratory bird species.

Avoid Using Pesticides and Other Chemicals

The most commonly used class of pesticides in the United States are called neonicotinoids or “neonics.” These systematic pesticides are fatal to insects and the birds that consume them. Other commonly used products like weed-killers 4-D and glyphosate (used in Roundup) can also harm birds and other wildlife.

Purchase Shade-Grown Coffee and Local, Organic Food When Possible

This step may be out of reach for many on tight budgets as food prices continue to rise. However, if it’s available to you, buying locally grown, organic food ensures you’re not supporting destructive farming practices like heavy pesticide applications and slash-and-burn agriculture. Shade-grown coffee leaves trees intact, providing critical habitat for birds that winter in South and Central America. 

Chipping Sparrow on a branch holding a twig (migratory birds)
Chipping Sparrow

Keep Your Cat Inside and Encourage Spay/Neuter Programs

It’s estimated that cats kill 2.6 billion birds in the United States and Canada each year. Keeping your cat indoors or building a “catio” can protect your cat from predators and save migratory birds. Spaying and Neutering are also critical for cats. It’s estimated that 110 million feral cats are now in the United States and Canada. These cats lead short, harsh lives and are thought to cause about 2/3 of the cat’ bird kills in the United States.

We may not be able to fix the world, but we can take small steps to improve it. Picking a few simple tasks off this list can lessen the stress on migratory birds this fall and help preserve them for generations to come. 

Saving the Past for the Future