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What Perennials and Shrubs To Plant in Fall

Summer perennials and potted shrubs are great to plant in fall!

“Perennials (both woody and herbaceous) are shifting energy from their tops to their roots, preparing for their fall underground growth spurt.” -Russell Stafford

Gardeners tend to do the bulk of their planting and planning in spring when the horticultural hormones are running high. For many plants and purposes, however, fall is the perfect time to get down to some serious gardening. The best time, in fact.

Fall Growing Conditions

Fall growing conditions tend to be cool and moist–just perfect for new plantings.

Consider the conditions in fall. Soil and air temperatures are typically moderate, beneficial underground microflora are active, and soils retain moisture longer (thanks to the cooler air and lengthening nights). Plants, too, are undergoing favorable changes. Perennials (both woody and herbaceous) are shifting energy from their tops to their roots, preparing for their fall underground growth spurt. Deciduous plants are shedding their leaves, removing their main source of water loss and drought stress. On all fronts, things are geared for root growth, for as long as soil temperatures remain conducive (above around 40 degrees F).

Plant a hardy tree, shrub, or herbaceous perennial now, and its roots will proliferate (as conditions allow) until spring, gathering energy and preparing for a prosperous new year. Compared to an equivalent plant installed next spring, it will have a far more extensive root system, already adapted to the conditions on (and in) the ground. It will grow faster, tolerate drought better, and in almost every other way out-perform its spring-planted kin.

Bulbs for Fall

Hardy spring bulbs must be planted in fall. (Image by Jessie Keith)

Bulbs (including the rhizomes, corms, etc. that go under this term) are a special case. Most hardy spring-blooming bulbs absolutely require at least a couple of months in chilly, moist soil to stimulate rooting and develop and extend their flower buds. These are the bulbs for fall planting–crocus, daffodils, tulips, and hyacinths are among them. Don’t worry about planting them late, especially if you find bags of bulbs on sale in late October. Bulb planting into late November is just fine as long as you can work the soil. Adding a quality bulb fertilizer at planting time will help them flourish.

On the other hand, some bulbs spend winter in a rootless quiescent state and take well to winter dry-storage and spring planting. Many of the latter are frost-tender things such as dahlias, but the winter-dormant group also includes some hardy “bulbs” such as roscoeas and crocosmias.

Plants You Should Plant in Spring

Balled and burlapped shrubs and small trees should be planted in the spring, not fall.

As with all things horticultural, a few provisos apply. Most of the above advantages are nullified in the case of bare-root or balled and burlapped (B&B) plants, which lose many of their roots during harvesting. With their reduced underground resources, they may lack the capacity to replace water lost from stems and leaves during cold windy weather. Fall-planted bare-root and B&B evergreens are especially prone to winter damage. Severely root-bound container-grown plants do relatively poorly with fall planting, for the same reasons. In contrast, container-grown plants have relatively extensive root systems, buffering them against winter weather.

Fall perennials, like Japanese anemones, prefer springtime planting. (Image by Jessie Keith)

Additionally, some plants that hit their prime in summer and autumn tend to languish if planted in fall, whatever the condition of their roots. Many warm-season grasses and fall-blooming perennials, for example, prefer spring planting. Marginally cold-hardy plants may also benefit from spring planting, which gives them more time to establish before heading into their first winter. Small perennials and shrubs in little pots may also need the headstart of spring planting to grow and set ample roots by fall.

Fall Planting Tips

Make sure that potted plants do not have any congested or girdled roots as this will limit fall root growth.

Planting at least 6 weeks before your last frost date will give perennials and shrubs plenty of time to set new roots (click here to determine your last frost date). Whatever you plant this fall, be sure to provide the conditions for optimal rooting. Dig a planting hole as deep and several times as wide as the root ball. If the soil is excessively heavy or sandy, dig an even wider hole, and generously amend the backfill with Fafard® Premium Topsoil. Tease the surface of the root ball to loosen any congested or girdling roots. After planting and watering your new prize, apply a layer of compost topped with two or three inches of a porous mulch such as oak leaves, pine needles, or shredded bark. This will blanket the roots from drought and cold, extending their season of growth. Come spring, you’ll have a well-rooted plant, ready for takeoff.

*Fall is also an ideal time to divide and plant summer perennials! (Click here to learn more about perennial division.)

Ten Tips for Beautiful Container Gardens

Ten Tips for Beautiful Container Gardens Featured Image
Good care will keep your potted plants looking pretty.

You have purchased your pot, invested in potting soil, planted up your plants, and your container garden is well underway. In the cool of late spring, as container plants are rooting in, there are few stresses to disrupt your plantings. But, as plants grow and the summer heat ramps up, lots can go wrong. Here are tips for getting it all right.

The first half of successful container planting starts in the planning stages, by choosing the right pots, plants, soil, and fertilizer. The second half is knowing what to do to keep your container gardens looking great. Here are our top ten tips for container care from start to finish.

Pre-Planting Container Garden Tips

Colourful high-fired quality ceramic pots
High-fired, quality ceramic pots hold water well and overwinter better. Lighter-colored pots stay cooler in hot weather.
  1. Choose the right pot – Large containers made of the right materials helps plants grow more happily through summer. Big pots hold more water, provide more root space, and remain cooler to encourage good growth through the hottest summer days. Pots made of water-impermeable materials, such as stone, glazed ceramic, plastic, or resin, hold water better. TerraCotta and porous cement pots wick water away from roots because they are porous, so they are better suited to drought-tolerant plants or succulents. Containers that are light in color are better for sunny plantings because they reflect the heat of the sun. Pots must drain well and have a saucer, internal reservoir, or basin to capture excess water. Those with a self-watering base must have an overflow hole to protect against the possibility of overwatering.
Fafard Ultra Outdoor Planting Mix pack
Metal bowl planter with Calibrachoa, sweet potato vine, Bacon, and geraniums
Overstuffed containers, like this metal bowl planter with Calibrachoa, sweet potato vine, Bacopa, and geraniums, look good in early summer but are often overcrowded by midsummer.
  • 3. Choose the right plants and numbers. Will you place your containers on a sunny patio or window box, shaded porch, or bright, windy veranda? Is your summer climate hot and dry or mild and cool? The plants you choose must grow well in their destined location and in your local climate. Gardeners planting for sun must choose heat and drought-tolerant plants (click here for a list of Waterwise container plants), while shade-loving plants such as Begonia, Browallia, Impatiens, Torenia, and ferns are good choices for pots in partial to full shade (click here to learn more about growing Torenia). Consider the final size of each plant when designing containers, and do not overstuff the pots. Crowded plants compete for space, light, water, and nutrients, which causes them stress. Before planting, read about your plant’s needs and space them properly to ensure their best performance.
  • 4. Choose the right fertilizer. Gardeners with little time should choose an all-purpose slow- or continuous-release fertilizer to apply at planting time. Vegetable and fruit containers should be fed with plant food specially formulated for edibles. Water-soluble plant food can give plants an extra boost to encourage renewed growth and flowering midseason–particularly after plants have been trimmed and deadheaded.
Hanging summer annuals
Most summer annuals cannot be planted outdoors until the threat of frost has passed.

Post-Planting Container Garden Tips

Watering plants
Good watering technique is essential to successful container gardening.
  • 6. Know when and how to water. Good watering technique is all about common sense. Most garden flowers like lightly moist soil. If the soil is too wet for too long root rot will occur. If it’s too dry for too long plants will begin to wilt and die. When conditions are sunny, dry, hot, and breezy, plants use and lose more water (drawn up through their roots and lost through their leaves) and need more water. Likewise, when it has been rainy, cool, and still the need for water is reduced. Feel the soil before you water to determine if more is needed. If it is needed, irrigate until it flows from the bottom of the pot to ensure all the roots get moist.
Outdoor plants
Well watered and fertilized plants will look lush and flower and fruit well.
  • 7. Know when to fertilize. Slow- or continuous-release fertilizer formulated for flowers makes feeding easy because applications are needed every few months, depending on the product. Apply at planting time and then as directed. Water-soluble fertilizer will encourage further flowering and growth during the height of summer. Containers also need a boost of water-soluble food after they have been trimmed back in mid- to late-summer. Proven Winners offers both a premium continuous-release and water-soluble fertilizer that we recommend for flower-filled containers.
Trimmed petunias
Many petunias continue looking good and blooming for longer if they are trimmed back later in summer.
  • 8. Know if and when to prune and deadhead plants. To maintain any plant properly, read about its care. Some flowering plants are self-cleaning, such as sweet alyssum, Supertunia petunias, and Profusion Zinnias, while others, such as old-fashioned petunias and dahlias, need to have their old blooms removed to make way for new. Old-fashioned petunias, calibrachoa, and verbenas can become leggy, less productive, or overtake the pot as the summer wanes. Cutting the old stems back can rejuvenate growth and flowering for fall.
Old summer containers with fall elements and flowers
Reviving old summer containers with fall elements will give them a needed seasonal boost.
  • 9. Know if and when to replace seasonal flowers. The pansies and stocks of spring often die back in the heat of summer and need replacement with warm-season summer flowers. Summer annuals that begin to look tired by early fall, like marigolds or traditional petunias, should also be replaced with seasonal pansies, peppers, or ornamental kale to keep containers looking great. (Click here to learn more about container gardening with ornamental peppers.) Don’t be afraid to replace struggling annuals when they start to visually bring a container down.
Winter pot in snow
Be sure that winter pots are crack-resistant.
  • 10. Know how to overwinter pots. Be sure you choose the right pots if you want to overwinter containers outdoors (click here to read about overwintering containers). If your pots contain small shrubs or perennials, place them in a protected spot. Seasonal containers can be placed in a garage, basement, or under a dry porch where they will not become damaged by the freezing and thawing of winter.

Once you have the basics down, monitor your containers, protect them from pests and diseases, give them good care, and they will reward you with season-long beauty.