Creating an annual summer flower border
Creating an annual border is one of the most rewarding projects in gardening, within a few short months you can create a blaze of colour in your garden. Its quite a lot of work as all the seeds are grown from directly sown seeds but its well worth the effort.
- Alyssum (Lobularia maritima)
weet alyssum seeds may germinate in as little as four days, maturing quickly to produce masses of tiny fragrant flowers for your spring garden. Start them indoors five or six weeks before the last frost, or outdoors after frost. You don’t need to cover the seeds, just sow them thickly and press them lightly into the soil with your finger. Use a spray bottle to keep the seedbed moist until the plants germinate.
Sweet alyssum grows 3 to 9 inches tall and makes for a good edging and bedding plant. If you shear the plants back after the first bloom, a second flush of flowers follows. The flowers often fade, though, in the heat of summer.
- Celosia or Cockscomb (Celosia argenta, C. cristata)
This annual doesn’t enjoy the popularity of sunflowers or marigolds, but celosia’s unusual blooms that may resemble brain coral or feathers deserve a featured spot in every sunny garden. Although the seeds are tiny, they have a quick and high germination rate, and the plants may even self-sow in favorable areas. Start the seeds indoors six to eight weeks before the last frost. Sow three to four seeds per pot. Press the seed lightly into the soil to ensure contact and keep moist.
The celosias commonly planted as garden annuals are usually somewhat complicated hybrids of two or more species, but the cultivars are generally categorized into four groups:
Plumosa Group: Often called feather celosias or cock’s comb, this group has feathered, bright red flowers.
Cristata Group: Cultivars in this group have crested flowers with convoluted ridges that resemble brain corral. Flowers can be red, purple, or pink.
Childsii Group: This group, rarely sold at garden centers, has rounded flower heads that resemble twisted balls of yarn.
- Cosmos (Cosmos sulphureus, C. bipinnatus)
Cosmos flowers are as tough as nails from the day they germinate until fall’s first frost. Plant them once, and then watch each year for the ferny foliage that will let you know the self-seeded plants have volunteered in your garden again. Sow them directly in the sunny garden anytime in the spring; the plants know when to germinate, so these flowers are truly a no-brainer for beginners.
There are two forms of annual cosmos: C. sulpherous is an upright daisy-like flower that grows 1 to 3 feet tall, with yellow-orange flowers. C. bipinnatus has delicate threadlike foliage and daisy-like flowers of pink, red, or white. It can grow to 4 feet.
- Hyacinth Bean (Lablab purpureus)
Hyacinth bean is a beautiful flowering vine that’s easier to grow than a weed. This plant will cover your chain link fence or pergola for the summer, without self-seeding everywhere or becoming a nuisance. Push the plump seeds just under the soil’s surface when day temperatures average 75 degrees Fahrenheit and keep them evenly moist until germination occurs, about 10 days later. The vines will be a source of interesting pods and flowers for the vase by late summer.
The seeds inside the bean pods can be collected in the fall for spring planting, but be aware that they are toxic unless thoroughly cooked.
- Impatiens (Impatiens walleriana)
Although impatiens seeds are tiny, avoid buying the pelletized version of the seeds covered with a substance that makes them easier to handle. This coating slows down germination considerably. Impatiens need light, warmth, and moisture to germinate. Sow seeds directly on top of the soil indoors about two months before the last frost. The well-branched plants will light up your shade garden all summer. Planting directly in the garden is less practical, since the plants take quite a long time to mature into flowers—about 3 months.
For some time, impatiens vanished from garden centers because of downy mildew, a devastating fungal disease that killed virtually all seed stock plants. Recently, however, several disease-resistant cultivars have been developed, so you can once again use this plant freely in your shady garden beds.
- Marigold (Tagetes spp.)
Most of the familiar garden varieties of marigolds fall into one of three species:
African marigolds (Tagetes erecta): These have large pompom flowers. The plants can grow to 4 feet, and the flowers can be as much as 5 inches across. Colors are various shades of yellow and orange.
French marigolds (Tagetes patula): French marigolds have the longest bloom periods, and the plants tend to be short and bushy. They have purple-tinged stems with double flower heads in yellow, orange, and mahogany, about 2 inches across.
Signet marigolds (Tagetes tenuifolia): These look much different than other bedding marigolds, with lacy leaves and small, single, daisy-like flowers. They come in yellow and orange.
If you’ve had trouble growing marigolds from seed in the past, try growing some of the French varieties, which are more disease-resistant than the American types. ‘Queen Sophia’ is an All-America winner to try. Seeds germinate in less than a week in warm, moist soil. It takes about 8 weeks for plants to bloom from seeds, so you may want to start them indoors.
- Morning Glory (Ipomoea purpurea)
Don’t be intimidated by the hard seed coats of morning glories. Just soak them overnight in warm water, and plant the swollen seeds under a quarter-inch of soil indoors two weeks before your last frost. Make sure the transplants have something to cling to when you set them out. Are you a night owl and not a morning person? Just swap morning glories for moonflower seeds and get the same results.
Morning glories grow quickly when planted directly in the garden, but for a headstart on blooms, you can start them indoors six to eight weeks before the last frost date.
- Common Nasturtium (Tropaeolum majus)
What’s not to like about nasturtiums? They’re edible, they scramble over eyesores in the landscape, they have interesting foliage and brilliant flowers, and they thrive on neglect. The size of peas, nasturtium seeds are easy to handle and plant. But they don’t like transplanting much, so stick them in moist soil in a sunny spot as soon as the danger of frost is past. Or, start them indoors about four weeks prior to the last frost.
Nasturtiums are a complicated group featuring many cultivars derived from hybrids of different Tropaeolum species. There are both low mounding types and vining varieties within this group, so carefully research the types of seeds you buy to make sure you get what you want.
- Sunflower (Helianthus annuus)
There’s a reason these flower seeds are included in every pre-packaged children’s garden kit you’ve ever seen. Sunflower seeds are raring to go as soon as a child’s pudgy finger pushes them into warm, moist soil. These seeds are best started directly in the ground outdoors, as the seedlings get large and gangly fast in a little jiffy peat pot. If you must start them indoors, give them a strong light source to keep them stocky.
Different sunflower varieties have different growth habits, from about 3 feet to as much as 10 feet—make sure to buy the variety appropriate for your needs. Leave the flower heads in place after they fade to provide food for birds.