When you think of having autumn colors in your landscaping, do not forget about planting fall flowers. Fall foliage trees or shrubs with colorful autumn leaves are king, but perennials can add much color, and annuals are an inexpensive alternative. You may associate annuals with late spring (everyone gets the planting bug then), but fall planting with tender annuals is the mark of the true lover of great landscaping. For success in enjoying them in the autumn landscape, though, you need to plan no later than August.
Growing fall flowers in the garden will improve a landscape that is already graced by fall foliage trees. But if your landscaping lacks such trees altogether, planting fall flowers takes on even greater importance. The color display put on by these annuals and perennials is a great addition to the non-living autumn decorations in your yard like carved pumpkins, scarecrows, or scary ghouls. Learn about some of the best choices, plus tips on timing and on saving money.
When Should You Buy and Plant Fall Flowers?
Do not wait until autumn to buy flowers unless you live in a warm climate. Planting them too late shortens the time you have to enjoy them. Yet, even in the North, it is usually too hot to plant through the first part of August.
The window of opportunity for planting can be quite small, and there is usually no set date for planting, even for particular regions. You must play it by ear.
Some summers, a rainy period arrives in mid-to-late August, giving you the perfect opportunity for planting. Other summers, a late August planting would still subject your transplants to too much heat-stress, and it would be better to wait until early September.
There is also the question of what plants are available at this time (as the summer wears on, few garden centers will be carrying your favorite annuals); buy them no later than early August.
Hardy and Tender Choices
Plants that will survive the first frost, such as chrysanthemums, flowering kale, and flowering cabbage, are great choices for fall plantings. All provide the landscape with color well after the first frost. But do not be afraid to mix in annuals, too, including:
- Marigolds (Tagetes)
- Red salvia
- White alyssum (Lobularia maritima)
- Nasturtium (Tropaeolum majus)
- Pansies (Viola; treated as annuals in the North)
- Snapdragons (Antirrhinum)
- Celosia argentea var. cristata
The contribution of annuals will be brief but spectacular. Marigolds are one of the best picks because they bloom in the classic autumn colors: orange, yellow, gold, and so on. The two most common groups of marigolds are the French marigolds (Tagetes patula) and the African (Tagetes erecta). In each case, the common names are misnomers, as the marigolds are New World plants.
If saving money, you may be questioning the wisdom of planting such tender plants as marigolds for fall, since they will be dead in a few weeks. It would be a waste of money if you were getting them at springtime prices. But there is a way of avoiding paying top dollar for them.
How to Get Inexpensive Flowers
You can find flowers that will not break the bank in July and August. By slashing prices after prime time for annual sales has passed, garden centers can unload leggy annuals that they could not sell in spring. Ideally, they want to move these bargain-basement flowers by July and may even continue to carry an inventory of cheap flowers in August.
Flowers in the "leggy group" may not look like much when you buy them, because they have been sitting in nursery flats for too long. But they are still a great bargain because they can be revived if you follow a few simple tips. Check the undersides of the leaves first to make sure the plants are bug-free. It is too hot to plant these flowers in July, but that should not stop you from buying them. Go ahead and purchase the annuals, but do not plant them in the ground yet. Instead, transplant them into containers. Containers can be moved in and out of the sun, based on how your annual is holding up to the summer heat. You simply do not have this flexibility with annuals planted in the ground.
So, resurrect those poinsettia pots you have been throwing behind the garage after every Christmas, disinfect them, and use them as "sick bay" to nurse your bargain-basement plants back to health. To disinfect, soak them for several minutes in a solution of one part bleach to nine parts water, then wash them as you would kitchen pots (with a sponge, hot water, and dishwashing liquid).
When you knock the annuals out of their flats, check the root ball. If you have wall-to-wall roots forming such a dense mat that soil is not dislodged even when you squeeze it, then you have a root-bound plant. All is not lost, though. Before transplanting a root-bound plant, break up that dense mat by scoring all around the root-ball with scissors. It seems harsh, but this is a case where a little corrective surgery can do wonders.
Also, many annuals respond well to a good trim. You can revitalize everything from alyssum to petunias by cutting off the top half of the current growth (stems, leaves, and flowers). You almost must do this if your annuals are leggy.
During August you can nurse your bargain-basement annuals, getting them ready for fall planting. When temperatures cool later in the month or in September, transplant them out of their containers and into the ground for an eye-catching display of fall flowers.
Hope for Brown Thumbs
Brown thumbs will be glad to hear that there is another way to get seedlings for fall planting. Some retail outlets call in fresh recruits (seedlings started in summer) to put on sale as the dog days of August are coming to a close. These plants are just starting in life, so their foliage will still be fresh by the time they bloom in fall. This means that you will not have to nurse them back to health. You may pay a bit more for them than for the older, leggy plants, but they are still often sold at a discount, due to lack of consumer interest in annuals so late in the season.
Form, Texture, and Designing Visual Interest
While color comes to mind immediately, color is but one of the five basic parts of landscape design. Texture and form, for example, can also be used to improve your landscaping. When buying your fall flowers, if you make your choices to achieve contrast (either in form, texture, or both), your landscaping will have neighbors convinced that you are a real pro.
"Form" roughly means the shape of a plant. Visual interest can be achieved by using contrasting shapes. A mound-shaped plant such as Silver Mound (Artemisia schmidtiana), a perennial as far north as planting zone 4, gives you a good counterpoint to a spiky plant such as Dracaena indivisa. Both artemisia and dracaena are grown for foliage, not blooms; so add some fall flowers to such a planting to give it more color.
Landscape designers also take the form of individual parts of a plant into account. For instance, the leaves of one plant can have a form different from those of another plant. Leaf form and bloom form are central to "texture."
Form cannot be completely separated from the texture. The texture is mainly a visual matter in landscape design (not touch). It is dependent upon the form of the plant's blooms or its leaves. For example, the texture of the leaves of Senecio cineraria "Silver Dust," for example, with its toothed edges, contrasts greatly with a neighboring plant that has leaves with smoother edges such as Salvia splendens "Red Hussar." The former is perceived as having a more delicate texture.
Likewise, visual interest is provided by putting a relatively small-leafed, more delicate plant such as chrysanthemum (the hardiest will overwinter in planting zone 5) next to a plant bearing larger leaves, such as the coarse-looking flowering kales and cabbages.
The element of color plays a large role, too. Most people have specific colors in mind when planning a fall color scheme. Red-yellow-orange is a classic for the harvest season. Orange and yellow nasturtiums, lemon yellow French marigolds (Tagetes patula "Lemon Drop"), and reddish-purple plumed Celosia will set your fall gardens ablaze.
A metallic color scheme is also popular for fall: golds, silvers, and bronzes. Golden African marigolds (Tagetes erecta "F1 Gold Galore"), Artemisia ludoviciana "Silver King" (perennial to zone 5), and a bronze coleus (Coleus x hybridus) work well together.
Other perennial choices include:
- Montauk daisies (Nipponanthemum nipponicum)
- Goldenrod (Solidago)
- Joe Pye weed (Eupatorium maculatum)
- Bluebeard (Caryopteris; a sub-shrub often treated as a perennial)
- Autumn Joy stonecrop (Sedum 'Autumn Joy')