When the hot, hazy days of late summer descend, planters that looked lush at the beginning of the season can start to flag. Here’s how to help them make a successful transition from summer to fall.
To instantly improve a container’s overall appearance, trim off damaged, yellowed, crispy or chewed leaves. Thoroughly deadhead spent blooms (nip off all flower parts, not just the petals); this prevents plants from producing seed, which triggers them to stop flowering. Those that benefit include dahlias, geraniums, heliotrope, lantanas, marigolds, nasturtiums most petunias, salvias, verbenas and zinnias. Small-flowered plants such as bacopa, fibrous (wax) begonias, impatiens and portulaca and are too time-consuming to deadhead and are often self-cleaning.
Adjust water and fertilizer
By late summer, plants have matured and their roots fill the container, so they may need more frequent watering. And if you used a time-release fertilizer at planting time, it’s likely depleted. Check moisture levels often, and begin feeding plants weekly with a water-soluble fertilizer such as 10-10-10 or 15-30-15, diluted to half strength.
Give stragglers a haircut
For specimens such as calibrachoa, petunias, sweet alyssum and trailing lobelia that have grown lanky, a shearing may be in order. Cut back stems by one-third, then feed as above. Plants may look a bit sparse for a week or so, but they’ll soon put on new, more compact growth. Trailers, such as sweet potato vine or licorice vine, that have grown out of bounds benefit from a thinning. Cut back one-third to one-half of their stems to a few centimetres from the base of the plant.