Plant a garden all summer long, but watch out for watering – Chicago Tribune
“Is it too late to start a new garden this year? And should I water other plants in my garden?”
– Alfredo Gomez, Highwood
You can continue planting throughout the summer provided you pay close attention to watering. I have recently seen new garden installations struggling due to improper watering in some gardens. Most plants under stress have been grown in containers and dry out quickly in hot and windy weather.
It’s difficult to give you specific watering instructions as there are many variables that depend on a garden’s growing conditions. Gardens with sandy and well-drained soil will need more frequent watering to establish the plants, as the soil dries out faster than a heavy clay soil. Different plant species prefer different moisture levels. Perennials planted in a shady zone can compete with tree roots for water. The amount of sun or shade affects how much water is needed for those areas. Different zones can dry out at different rates.
The established plants that have been growing for over three years probably don’t need additional watering now. Plants newly installed in the last two to three years may benefit from extra water during dry spells this year. Any plants installed last year and this spring should be given priority.
Just watered some hydrangeas I planted in fall 2020 after seeing them wilt. Withering foliage is a signal to check if the plant needs watering. The hydrangeas are planted under an oak tree so they compete for water with the tree and surrounding perennials, and although the bed is shady, it dries out quickly.
Check the soil at the base of your plants to see how much moisture there is to help you decide if you should water. Plants show water stress with wilted leaves and leaves that turn a discolored color from green or yellow to brown when dry. For trees and shrubs planted as ball and jute trees and shrubs, water at the base with a hose to thoroughly wet the root balls during the first year or two of planting.
Don’t just rely on one sprinkler system. Even recently installed perennials will benefit from an occasional deeper soak with a hose while they are establishing in their first year. The foliage of evergreens can spill water from a sprinkler to the outside of the root ball, leaving it dry. As the tree establishes itself for the first two to three years, the roots will grow into the surrounding garden soil. In the first year, one thorough watering per week is generally sufficient for new ball and burlap plants.
Also, be careful not to overwater as I’ve seen gardens with soggy soil even during dry periods – a sign of overwatering, which can also stress and kill plants. Plants grown in containers may need to be watered a few times a week if the weather is hot and dry for the first few weeks after planting. Since the plants root into the surrounding garden soil, they dry out less quickly. Be sure to check them a few times a week after planting.
If you use an automatic sprinkler system or irrigate with a sprinkler attached to a hose, verify that all plants are getting adequate water by monitoring the soil and spot checking the root balls of the plants. Don’t assume your sprinkler system will provide the correct amount of water. Monitoring plants and soil moisture will help you provide the optimal amount of water for your new garden plants.
Proper watering is critical to success when seeding a lawn and I see many gardeners fail at it. The grass seed needs to be kept moist by frequent, light watering one to three times a day until it germinates in about two weeks. Allowing it to dry out during this time can drastically reduce seed germination. A light layer of compost can help retain moisture for the grass seeds.
For more plant advice, contact the Plant Information Service at the Chicago Botanic Garden at [email protected]. Tim Johnson is Senior Director of Horticulture at the Chicago Botanic Garden.