My Leaves Have Brown Spots!

My Leaves Have Brown Spots!

Although the regular rain has been welcomed after last summer’s drought, so far the spring and early summer weather on Cape Cod has been cool and damp. This combination is pretty much a prescription for fungal problems. We’ve had customers come in with fungal conditions on lawns, perennials and shrubs. Here is a rundown of what you might be seeing in your landscape:

Blackspot is starting on roses.
Peonies have black buds that won’t open.
Lilacs have black leaf edges and flowers that brown quickly.
Hydrangeas have black spots on their leaves.
Apple trees show darkening foliage or have rusty spots on the underside of leaves.

Here’s the bottom line: none of these will kill the plants but they may look badly as a result. You can spray with a fungicide, but that only helps protect unblemished foliage…it won’t cure already infected plant tissues.

In addition to these conditions, this cool and damp weather is perfect for Impatiens Downy Mildew to be active on the regular Impatiens. So if you’ve planted regular impatiens and they start dropping their leaves and showing bare stems, chances are the downy mildew has hit once again.

Peony buds get a form of botrytis in cold, damp weather that can cause the flowers to shrivel and die before they can open.  If this happens to you, start spraying with Serenade next year as the flower buds form in order to protect them.

Peony buds get a form of botrytis in cold, damp weather that can cause the flowers to shrivel and die before they can open. If this happens to you, start spraying with Serenade next year as the flower buds form in order to protect them.

Spraying roses regularly will slow blackspot although it won't cure it. Use a fungicide labeled for blackspot on roses - we have several so come into the store to talk about the various options.

Spraying roses regularly will slow blackspot although it won’t cure it. Use a fungicide labeled for blackspot on roses – we have several so come into the store to talk about the various options.

Here is how leaf-spot fungus looks on Annabelle Hydrangeas. This is a cosmetic problem - the plant won't be harmed long term.

Here is how leaf-spot fungus looks on Annabelle Hydrangeas. This is a cosmetic problem – the plant won’t be harmed long term.

Apple trees are prone to several fungal problems in wet, cool weather. Those that tend to get cedar apple rust will show symptoms more quickly.

Apple trees are prone to several fungal problems in wet, cool weather. Those that tend to get cedar apple rust will show symptoms more quickly.

Lilacs get another form of botrytis that causes leaves to be spotted or have black edges. In constant moisture the flowers can brown as well.

Lilacs get another form of botrytis that causes leaves to be spotted or have black edges. In constant moisture the flowers can brown as well.

There are several fungicides that can help slow the progression of fungal problems. From organic sprays such as Serenade to systemic products, we will help you get what you need to slow diseases while we wait for the sun to return!

There are several fungicides that can help slow the progression of fungal problems. From organic sprays such as Serenade to systemic products, we will help you get what you need to slow diseases while we wait for the sun to return!

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