When should you remove leaves from landscape beds?
While leaving some leaves in your beds to act as a natural mulch, or on your lawn for organic matter, can have benefits, it can also come with some hidden risks. Plant pathogens and pests that may have reeked havoc on your trees over the last year, can survive on the leaf litter that falls to the ground. If your trees or large landscape shrubs have suffered from specific fungal or pest infestations, it may be time to rake out those leaves!
What’s the harm?
Leaves left lying on your lawn that have not been chopped into smaller particles by the mower will not break down quickly. Leaves left in landscape beds can carry spores and harbor pests. Oak leaves are especially slow to decompose and have a tendency to mat together, hold in moisture and trap air, creating optimum conditions for fungal spores to take hold. Harmful fungal spores produced on leaf litter are particularly devastating to brand new lawn foliage just coming out in spring.
Some of these diseases only cause problems on living plants, in which case they are fine to be composted or mulched into the lawn using a mulching mower. Or, put into the leaf chipper and used as a fine leaf mulch. However, leaves infected with some diseases must be completely removed from your property to prevent spreading the disease further the following year.
Diseases to watch out for
Powdery mildew, for instance is one such disease that affects plant leaves, particularly crape myrtle, in our area. Its name is quite descriptive, as trees and shrubs affected look like they're covered in a grayish white powder. Even though crape myrtle leaves are small and fast to break down, allowing them to stay on the ground beneath and around the tree will set you up for a disease problem all over again.
Leaf spot diseases, like those that commonly affect Photinia and Indian Hawthorn in the Dallas Ft. Worth area, are another great example of where good sanitation makes a difference. Leaf spots grow larger with time, eventually causing leaves to drop. Just like the powdery mildew, leaf spot spreads from season to season. If it isn’t removed from the property, it will begin again once the warm damp air arrives in spring.
Is your tree in the right place? Remember that plants in the wrong place, such as a sun loving plant in too much shade, will be more likely to suffer from fungal diseases. If you find that your trees have expanded and are beginning to block much of the sun your shrubs and perennials might have received in the past, these are your first candidates for careful clean up. When these sun loving trees and shrubs are watered without the requisite amount of sun to dry their leaves, fungal diseases will have a quick and easy time settling in.
Best to keep an eye out for fungal problems this time of year and have a trusted landscape or tree care pro out to your property for proper diagnosis and treatment. Good landscape maintenance will put a stop to many of these diseases caused by haphazard pruning, plant cleanup and lack of maintenance.
A healthy landscape brings so much vitality and aesthetic beauty to our neighborhoods. We're here to help you identify situations that can have potential negative impact on your property to keep your trees in the best of health.