Most of us are actively cleaning up the perennial beds, vegetable garden, landscape beds and even getting our first lawn mowing out of the way because the whole yard looks better when that’s done. However, not everyone views this time of spring cleaning the same way. Entomologists, for example, are in favor of leaving the overwintering bits up, as many of our insects use that as a means of survival; while plant pathologists view that same garden debris as a source of future disease in your yard.
The following is based on an excerpt from the first Home, Yard and Garden Pest newsletter by Maria Turner, University of Illinois Extension State IPM Specialist. Typical spring weather that is cool and wet favors fungal growth. While disease pressure now may not be bad, Turner offers these tips to keep disease at bay.
- After major frost threat, remove old foliage from annual and perennial beds, grasses, and weedy areas. “Many diseases caused by fungal pathogens, such as black spot of roses, will overwinter on old, infected foliage. Tender new spring foliage is more susceptible to fungal infection than older, thickened leaves. Removing the old, infected foliage will reduce the amount of fungal inoculum that might otherwise infect in the favorable spring conditions.”
- Remove dead wood in trees and shrubs. “Most of the wood-rotting fungi and canker fungi invade stressed or injured wood. They will, however, move from a dead stem into the older wood in the same plant. Now is a good time to remove dead or cankered wood. It is easy to spot against the new growth. Examples include dead branches from Cytospora canker on spruce, rose cane cankers, and stems of redosier dogwood killed by winter stress and subsequent canker fungi. If you are removing dead wood from pears, disinfect pruners between cuts to avoid spreading potential pathogens such as the bacterium that causes fire blight.”
- Remove cedar apple rust galls now to limit infection or spread. “Cedars infected with cedar apple rust will be erupting soon so removing these galls now will reduce the infection in their broadleaves hosts. Also, pines infected with Diplodia can benefit from spring cleanup. Remove the dead stem tissue. Rake and remove pinecones where this fungus overwinters.”
Remember, it often is best to avoid putting any of this diseased debris in your compost pile or bin. While infected foliage should be safe if the composted material is allowed to decompose, when in doubt, find other means of disposing of diseased plant material.
Now you can see that gardeners will always have decisions to make and there will always be compromises with nature when it comes to those best management practices for insect, weed and disease management in the vegetable garden, flower beds and the trees and shrubs in the home landscape.