Creating a beautiful garden is a rewarding task, filled with exciting possibilities. The nicest compliment a gardener can receive from a friend or neighbor is, “You have flowers blooming all season – How do you do it?”

By Abby Lapides

[This article was first published in The Gateway Gardener Summer 2023 issue.]

Creating a beautiful garden is a rewarding task, filled with exciting possibilities. The nicest compliment a gardener can receive from a friend or neighbor is, “You have flowers blooming all season – How do you do it?”  Follow some of these techniques to keep your garden flowering all summer long into fall.

– Pinch back mums and other fall-blooming perennials such as aster and turtlehead to create bushier plants with more flowers. Plants should be cut back around July 4^th.

– Cutting off spent flowers of perennials and annuals, called deadheading, encourages more blooming. Deadheading diverts the plant’s resources from generating seeds into producing new blossoms.

– Divide and set our tall bearded iris in late July. Select only healthy outside rhizomes for replanting in newly prepared soil.

– If your annuals look spent and leggy, cut them back hard to about 4-6″ to encourage new growth. This will revitalize annuals such as petunias and million bells.

– Heavy rains will leech out fertilizers, especially in potting soils formulated for containers. If the color of leaves is a dark green the plant is fine; if the leaves turn to a light green there’s been a loss of nutrients and the plant requires fertilizer. Apply a slow-release fertilizer like Osmocote. It only takes minutes to apply, and one application will last the rest of the summer. For even more flowers, also apply liquid fertilizer at 1/2 strength following manufacturer’s instructions.

– No fertilizers should be applied to shrubs and trees after July 4, it may cause tender lush growth that is more susceptible to winter kill.

– Hibiscus and other houseplants wintered indoors need a good supply of water and fertilizer up until early October. If plants are pot bound, consider repotting them into a larger container, one size up. Repot plants by late August so they will be well established for bringing indoors later in fall.

– Fertilize mums, asters and other fall-blooming perennials for the last time in early August.

– Divide spring blooming perennials in late August when the temperature has started to cool down.

– If needed, cut back spring and summer blooming shrubs by early to mid August. Some trees and shrubs start to set buds at this time. If you cut the stems later in the season you risk losing your blossoms.

How to Water Like a Pro

Keeping plants watered is an essential task to creating a long-blooming and happy garden, yet sometimes we’re just too busy with other things. In St Louis we can pretty much count on a stretch of hot weather with little or no rain every summer. Here are some of my favorite techniques that make managing my gardens, containers, and houseplants a bit easier.

– Get your plants to absorb as much water as possible by watering them in the early morning. Later in the hottest parts of the day plants will absorb less water due to the heat causing more evaporation.

– Add mulch. Mulching helps keep the soil cool and moist and helps prevent weeds. Mulch can be shredded bark or other decorative mulches. Compost makes a great mulch as it also improves the soil. Although not the prettiest of mulches, grass clippings make a fantastic mulch for vegetable and flower beds.

– Remove weeds often. Weeds steal valuable water your plants need.

 – Vegetable and flower gardens need about 1″ of rain per week, but in extreme weather may need more. Water every day or every other day.

– Containers of flowers and vegetables may need deep waterings every day or every other day. Put your finger in the soil, about 2” down, to determine if water is needed.

– Newly planted trees and shrubs should be watered deeply when the soil has dried out. Keep a close eye on newly planted trees and shrubs for the first year or so.

– During prolonged dry spells established trees and shrubs may need occasional watering. Apply a deep watering over the entire root zone area until the top 6 to 9 inches of soil are moist.

Vacation Watering Tips

Ideally, you will have someone come over to water your plants while you are on vacation. If that is not an option, try these techniques that I use:

– For outdoor plantings place timers on your faucets to schedule watering with sprinklers and soaker hoses. This easy-to-do method works great for short or long trips. If possible, move containers in the shadiest spots while you are away.

– Cut off all flowers and flower buds on reblooming perennials and annuals before you leave on vacation. It will take some stress off the plants, and will rejuvenate them, giving you fresh blooms when you return.

IMPORTANT NOTE: Avoid light frequent watering as this promotes shallow root systems that dry out quickly causing plants to be more susceptible to summer heat and drought stress. Water deeply to train roots to grow deep in the soil where more water is available.

Abby Lapides is owner and a speaker at Sugar Creek Gardens Nursery. She has degrees from the University of Missouri, and is a member of the Landscape and Nursery Association of Greater St. Louis.