Weigelas are generally tough-as-nails plants that don’t run into much trouble with pests or diseases. That said, even the hardiest shrubs can have a bad day! To keep your garden looking its best, it’s a good idea to know how to spot and treat the most common culprits.
Keep an eye out for these three issues:
- Leaf spot disease
- Aphids
- Leaf nematodes (foliar nematodes)
– Dealing with Leaf Spot on Your Weigela
As you might have guessed from the name, leaf spot shows up as yellow, brown, or even reddish spots on your weigela’s foliage. This is actually a fungal disease that thrives in damp, humid conditions. To prevent it from taking hold in the first place, make sure you give your plants plenty of elbow room for airflow and pick a sunny planting spot.
If you notice those spots popping up, grab your shears and prune away the affected branches. A quick pro-tip: never throw these clippings in your compost pile! The fungus can survive the composting process and hitch a ride back into your garden when you fertilize later. Also, be sure to disinfect your pruners afterward so you don’t accidentally spread the spores to your other favorite plants.
For an extra layer of protection, you can treat the shrub with a copper sulfate solution. Using a fertilizer that contains copper sulfate can also help boost the plant’s defenses against future outbreaks.
How to Get Rid of Aphids
Aphids are a common garden nuisance, but they’re usually pretty easy to handle. Often, a strong blast of water from the garden hose is enough to knock them off. If they’re being stubborn, try spraying your weigela with a mixture of water and a little bit of mild dish soap or insecticidal soap. Just be thorough—make sure to spray the undersides of the leaves where those little guys love to hide. Repeat the process every few days until they’re gone for good.
Tackling Leaf Nematodes
Leaf nematodes are tiny roundworms that travel through water. If you suspect you have them but aren’t sure, try this little trick: crumble an affected leaf into a glass of water and wait a few minutes. If they’re present, you’ll see the tiny worms swimming near the surface.
You can spot a nematode problem when parts of the leaves start looking “glassy” or translucent. Over time, these spots turn into brown, angular patches.
Unfortunately, there isn’t a great “home remedy” for these pests yet. Your best bet is to prune off the infested leaves and stems immediately. For the next few weeks, water your plant sparingly and try to keep the foliage as dry as possible to stop the worms from spreading.
