7 Common Clematis Care Mistakes (And How to Avoid Them)

Growing clematis can give you beautiful climbing flowers that last for years. But many gardeners run into problems that stop their clematis from reaching its full potential. While these plants can grow well in many gardens, small mistakes in their care can lead to poor growth or few flowers.

I’ve helped many gardeners fix their struggling clematis plants, and the same issues come up again and again. In this guide, I’ll show you the most common mistakes people make when growing clematis and give you clear steps to fix them.

These solutions will help your clematis grow better and produce more flowers, whether you’re just starting out or have been growing these plants for years.

1. Planting in the Wrong Spot

Many gardeners put their clematis in spots with too much shade or sun. Clematis needs 6 hours of sunlight daily to bloom well, but their roots need to stay cool. Plant your clematis where its flowers get sun but its base stays shaded. You can put small plants or rocks around the base to keep the roots cool. Test your spot by checking how many hours of direct sun it gets before you plant.

2. Not Pruning at the Right Time

Each type of clematis needs different pruning times, and cutting at the wrong time can mean no flowers that year. Look up your specific variety – they fall into Group 1, 2, or 3. Group 1 needs pruning right after flowering. Group 2 needs light pruning in spring and after the first flowers. Group 3 should be cut back hard in late winter. Keep a note of your clematis type and when to prune it.

3. Forgetting About Soil pH

Clematis plants grow best in soil with a pH between 6.0 and 7.0, but many gardeners skip testing their soil. Buy a simple soil test kit from a garden store and check your pH. If your soil is too acidic (below 6.0), mix in some garden lime. If it’s too alkaline (above 7.0), add sulfur or peat moss. Test your soil once a year in spring to keep the pH right.

4. Poor Watering Habits

Many clematis die from either too much or too little water. These plants need steady moisture but can’t sit in wet soil. Water deeply once or twice a week instead of giving small amounts daily. Push your finger into the soil – if it’s dry 2 inches down, it’s time to water. Add 2-3 inches of mulch around the plant to help keep moisture steady.

5. Missing Early Support

Clematis needs something to climb on from the day you plant it. Many gardeners wait too long to add support, and the stems get tangled or break. Put a trellis or support in place when you first plant your clematis. Make sure it’s strong and at least 6 feet tall. Guide young stems onto the support with soft plant ties or twine. Check the ties monthly to make sure they’re not too tight.

6. Using the Wrong Fertilizer

Many gardeners use high-nitrogen fertilizers that create lots of leaves but few flowers. Clematis needs balanced nutrition with extra phosphorus for flowers. Use a fertilizer marked 5-10-5 or 3-15-3 (the middle number should be highest). Start feeding in early spring when new growth begins. Add fertilizer once a month until August, then stop to let the plant get ready for winter.

7. Ignoring Signs of Disease

Early signs of clematis wilt or fungal problems often go unnoticed until the plant looks very sick. Check your plant every week for stems that suddenly turn black or leaves that develop spots. If you see problems, cut affected stems back to healthy growth right away. Clean your pruning tools with rubbing alcohol between cuts. Make sure air can flow around your plant by keeping nearby plants trimmed back.