Take care of your trees and shrubs during the hot, dry days of August. I’m Lisa Hilgenberg from Chicago Botanic Garden with your gardening tips for the week.
Continue to water newly planted trees and shrubs planted if rainfall is insufficient. Watch closely for signs of scorch on tender new foliage — the margins of leaves turn brown and crispy — indicating lack of water or exposure to hot drying winds. Generally trees need 1- 2” of water per week.
Soak shrubs to a depth of 8”. Mulch helps prevent evaporation and keeps soil and thus roots cool in hot summer.
Avoid injuring roots when digging near trees and shrubs but suckers coming up from around the trunk should be removed. Care should be taken to not injure the bark and roots when using lawnmowers, weed whips, and edging tools.
Pruning is generally not advised this month, with the exception of shrubs that have just flowered. They should be are pruned immediately following their flowering.
Refrain from fertilizing trees, shrubs and roses after mid-summer. Evergreens can moved now so they have a chance to root in before cold weather arrives.
Lisa Hilgenberg is the Regenstein Fruit & Vegetable Garden Horticulturist. She teaches classes for the Joseph Regenstein, Jr. School of the Chicago Botanic Garden and mentors interns from the Garden’s urban agriculture programs in the summer. Lisa draws on a rich family farming tradition, having spent many summers on her grandparents’ farms in Iowa and Minnesota. You can follow Lisa on Twitter @hilgenberg8.