Should I remove leaves when pruning?
Written by
Benjamin Miller
Reviewed by
Prof. Martin Thorne, Ph.D.Taking into consideration that removing leaves and foliage when pruning is done judiciously. Healthy leaves contain the energy that a plant needs to recover from pruning effectively. I only remove foliage that is decaying due to a disease, such as black spot or mildew. I also remove any damaged leaves that have been torn off by the weather or pests. All undamaged green leaves should not be removed. They are the additional energy source needed to fuel new growth after the stresses of pruning.
Diseased leaves require specific management to prevent spreading the disease. Black spot fungus survives composting and can re-infect plants later. I seal infected leaves in plastic bags to dispose of them. Do not compost infected material with garden compost. Always sterilize pruners right after cutting infected material. This extra containment has stopped the black spot in my rose garden.
Identification
- Black spot: circular black spots with yellow halos
- Powdery mildew: white powder coating surfaces
- Rust: orange pustules on undersides
Removal Procedure
- Wear gloves to prevent direct contact
- Place directly into disposal bag while cutting
- Clean tools with disinfectant wipe after each leaf
Energy production renders healthy leaves essential for healthy growth. Photosynthesis keeps going during dormancy. I preserve every scrap of green leaf area. Green leaves create sugars for the roots and the buds. When too many leaves are removed, the plant is effectively starved of nutrients. I made that mistake one year ago, and it set back my roses.
Pruning in the fall necessitates another way of dealing with leaves. While plants are getting ready to go dormant, you can easily take off leaves. I do this when winterizing hybrid teas by stripping any remaining leaves from the plant. I do so because the leaves would be susceptible to fungal spores that overwinter and infect the plant the following spring. Regardless, be sure to disinfect the ground beneath the plants once you have stripped the leaves. This technique has essentially eliminated mildew from my garden each year.
New growth becomes stronger when leaves are properly managed. By saving leaves, you allow supporting bud growth to happen once pruning is done. I check saved leaves for a few weeks after cutting, and they should generally remain vibrant green without finger spotting. Otherwise, you can give some to your roses with foliar feeding if needed. Roses recover more rapidly in growth once this observation is incorporated into your decision-making.
Tool hygiene is key to avoiding disease transmission between plants. A simple practice is to wipe the blades with a 70% isopropyl alcohol solution. This is particularly crucial after you prune a diseased leaf. I carry alcohol wipes in my pruning kit. Clean tools protect all your plants in your entire garden. This simple practice spared my other plants from developing infection.
Read the full article: 7 Essential Steps for Pruning Rose Bushes
