Today’s Garden Ideas

Blackspot is one of 3 major diseases that can destroy a once luscious rose garden. Luckily, Blackspot is easy to get rid of. It looks like black patches on leaves and stems. Blackspot is fungus that really likes humidity and rain.

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Signs of Disease

The first signs of Blackspot are small black dots on the rose leaves. As they grow the dots become encircle by a yellow ring of dying tissue. As the fungus progresses the leaves turn yellow and fall off. If you check your roses weekly you can catch Blackspot early and treat effectively.

Like any other fungus Blackspot is made of spores that become airborne to fall on rose bushes. A Blackspot infected solid surface can also contaminate rose plants if it is brushed against the leaves. Blackspot spores can also be spread through water. In addition the spores will survive through the winter if infected leaves are left to incorporate into the soil.

Treatment and Prevention

There are 3 stages to treating Blackspot: early prevention, quick treatment, thorough clean up of infected leaves.

To prevent Blackspot spray your roses with one part lime to nine parts wettable sulfur in the winter. Keep a watchful eye on your roses when they begin to sprout new growth. As soon as your spy Blackspot infected leaves remove and detroy those leaves. If you are too late, or despite your best efforts, Blackspot decides to hang around start treating with a fungicide. Check with your local nursery for the most effective treatment for your area. Benomyl and Daconil are very effective in fighting Blackspot.

If you keep having a yearly recurring Blackspot problem with your roses prune them very low in the fall. Be sure to clean all leaves and wood from around your newly pruned plant to prevent Blackspot from returning.

To prevent Blackspot from returning try these natural remedies. Purchase your rose plants from a nursery with a good reputation. Roses from the roadside stands or a friend’s garden are more likely to carry Blackspot. Be sure to plant your roses so there is sufficient air circulation. Plant roses where air can flow around them. Use soaker hoses to water plants. If a plant has Blackspot it prevents water spray from carrying the spores to uninfected rose plants. Pick up and destroy all leaves on a Blackspot infected plant quickly to prevent Blackspot spores from settling into your soil.

If you want to prevent Blackspot using chemicals try a liquid sulfur lime mixture. Begin its application in early winter. You can also dust with sulfur alone to prevent Blackspot.

If your roses are seriously infected spray with fungicides. As a preventative begin this application in the spring before new growth appears. Then spray every 10 days. Copper fungicides, like Bordeaux mixture, work well against Blackspot

Because Blackspot can survive in the soil over the winter be sure to treat your soil, too. Spray with a lime-sulfur mixture evenly over the rose bush growing surface and surrounding soil. A spray of garden oil with zinc or copper sulfate can also wipe our Blackspot spores in your soil bed.

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Finally be sure to clean all your tools thoroughly after using them on Blackspot infected roses. Always wash your gloves and hands after working with diseased plants.

A small amount of diligence and easy early treatment on your part can go a long way to preventing a Blackspot epidemic in your rose garden. Luckily this Blackspot fungus is easy to treat and prevent. Just stay on your guard and your roses should stay beautiful and healthy through the growing season.