With planting beds readied for the summer season it’s time to take a look at openings in the garden and add annuals into spaces between perennials, ornamental grass, shrubs, and groundcovers.
Now is the time to make notes about shade or sun areas that could be made visually interesting with the addition of textural foliage or bold colors. High priority spots are usually entry walks and front foundation areas or planting beds around patios, and containers.
While perennials usually bloom for 7-10 days, annual plants will bloom for extended periods with some varieties dependably flowering from June through to the first frosts of October.
Tropical annuals with interesting foliage are worth seeking out at garden centers. I always put Swedish Ivy (Plectranthus sp) in large containers where its stems can cascade over the sides; look for the variety ‘Variegatus’ which has small white margins on its leaves.
Other great foliage plants include variegated licorice plant, chartreuse ‘Marguerite’ sweet potato vine or a purple variety, ‘Glacier’ variegated ivy (Hedera helix), and coleus.
Coleus is in a class of its own. There are many color variations to choose from but check tags as some are sun tolerant while others are not. During the growing season you need to pinch out the flowers to promote lateral growth so that plants become big and bushy and continue to be vigorous. With regular watering and some light fertilizing in mid season they will be lush and gorgeous all summer long.
For a dramatic combination pair ‘Dark Star’ coleus with ‘Black Cherry’ supertunia, pink petunias and begonias.
One of my favorite annuals is ‘Diamond Frost’ euphorbia which blooms until frost and forms a frothy white mound covered in tiny white flowers that are airy and delicate. These plants look great among perennials like purple salvia ‘May Night’ and pale yellow coreopsis ‘Moonbeam.’
A tender salvia that’s worth growing for its unusual flowers is ‘Black and Blue’ (Salvia guaranitica). At 30-40” tall this is a stately multi-branched plant which can attract hummingbirds.
Salvia ‘Victoria’ is another long blooming cultivar which makes a good bedding plant. Look for this growing in the formal gardens at Shelburne Farms in the elliptical bed. A lovely blue that makes a statement when planted in mass, this is a classic annual to combine with orange marigolds or dwarf zinnias.
Like to cut flowers? Zinnias are the best annuals for the cutting garden. Tall and multi-branched, they may need stakes so that they don’t flop over but they’re worth the effort. With flowers in shades of cream, white, chartreuse, orange, purple, and a range of pink and red, they’re easy to grow and make good plants for a children’s garden.
Mexican sunflower (Tithonia rotundifolia) tops my list of gorgeous summer annuals – planted in a sunny spot the cheerful orange blooms attract butterflies and bees and make a great quick bouquet for a Mason jar.
Charlotte Albers owns Paintbox Garden, a landscape consulting and design business in Shelburne. Contact her at paintboxgarden.com.