University of Illinois Extension

Flower Garden Care - Little Things Make a Big Difference

Now is the time to start thinking about what your flower garden will look like in late July and August, said Sharon Yiesla, a University of Illinois Extension horticulturist.

“By mid-summer, flower gardens often look a little tired,” said Yiesla. “But there are some things you can do to keep your garden looking great all season. Some of these practices are preventative maintenance and can be put in place now; others can be implemented as parts of the garden start to fade.”

Watering, she noted, is essential to maintaining the garden.

“Keep plants watered consistently during the heat of summer,” Yiesla said. “On average, plants need one inch of water per week. In the heat of summer, they may need one inch every five days. The one inch should be applied all at once to ensure a good, deep watering that allows plants to be fully hydrated.

“Doing it all at once also allows us to water within the water restrictions of most municipalities. Avoid wetting foliage as this can lead to fungal diseases.”

A two to three-inch layer of mulch can reduce weed problems, conserve moisture, give the garden a better look and reduce erosion.

“It can also reduce stress on the plants,” she said. “Bare ground can really heat up, causing the root area to be hot, which adds stress to the plant. Mulch acts like an insulator and applying the mulch before temperatures become excessive will prevent soil from being too hot.”

Before applying fertilizer, home gardeners should ask: do the plants need it right now?

“Plants under drought stress need water, not fertilizer,” said Yiesla. “Be sure that plants are fully hydrated before even thinking about fertilizer. Always make water the priority. Using a time-release fertilizer can be a good practice, since the fertilizer is released slowly over a number of weeks rather than all at once. This can reduce fertilizer burn.”

Deadheading annuals will produce more flowers. When deadheading, remove the entire flower, not just the spent petals.

“If you do not remove the base of the flower, the plant will try to make seeds instead of more flowers,” she explained. “Deadhead perennials to prevent seed production and strengthen the plant.”

There may be some perennials that the home gardener might not want to deadhead because the seed will feed the birds or the seed head may be something to use in a dried arrangement, she added.

“Think about what you want to do with each perennial before you begin deadheading,” she said.

It is important to keep up with weeding because weeds can quickly outgrow desirable plants. Mulch to control weed seedlings. Cultivate shallowly to destroy existing weeds. Keeping weeds out of the garden not only reduces competition to desirable plants, but also keeps the garden looking good.

“You can also think about rejuvenating ‘tired plants,’” Yiesla said. “By mid-summer it is common to see some of our perennials looking a little ragged. Consider cutting these plants back to encourage a flush of new growth. The plant may not flower again, but at least it will look green and fresh instead of brown and battered.

“Cut plants back based on how they look. Some perennials may need just a trim, while others may need to be cut back all the way. Be sure to follow up with watering to encourage that flush of new growth to develop. Dry plants don’t grow much.”