Carrie Barre-LiBaire's Gardening Column

Down to Earth Gardening

Well, it seems we are actually going to have a summer after all! The cool rains the last week of June and the heat we have experienced since have made it prime time for fungal diseases to start occurring. We have seen Anthracnose on both Oak and Ash trees this week. Anthracnose is a collective name for a variety of fungi that affect shade trees. You may notice that the leaves on your tree have brown, dead spots. As the disease continues, these leaves become heavily spotted, curled and twisted. In severe infections this will also cause the leaves to drop. One thing to note is that this disease progresses upward and outward from the lower inner branches of the tree. This is important because other, more severe and deadly diseases will start from the top of the tree and work its' way downward. While unsightly, Anthracnose does not permanently damage trees, so spraying a fungicide is not necessary. The best thing to do is make sure your trees are watered if dry, mulch them and make sure to rake up and properly dispose of any fallen leaves this year, including fall leaf drop.

Another issue that is just heating up is spider mites on spruce trees. Spider mites are related to both spiders and insects. If you are seeing sticky webbing and the spruce needles are yellow, brown or dirty looking, you may have them. The damage to the needles occurs from the spider mite sucking them. You can check for them yourself by holding a white sheet of paper under a suspect branch and tapping it hard. If you see little flecks drop off and start crawling around, those are the spider mites. Spider mites thrive in heat, so if you are sure you have them you can spray with insecticidal soap or horticultural oil, although repeat applications will be necessary. If you have a severe infestation you can use a pesticide called a miticide. You may also find insecticides that specifically list mites on the label.

As the temperatures rise, it is important to keep an eye on your rain gauge. Make sure your hard work doesn't die on you by watering your container gardens every day, and if it's hot and windy, twice a day. Your lawn needs an inch of water per week and watering early in the morning is the best time to do this if we don't have sufficient rainfall. Avoid watering in the evening so you don't invite turfgrass disease into your lawn.

The Douglas County Master Gardeners hold many events throughout the year. One of our most popular and enjoyable events is the Tour of Gardens. It will be held Sunday, July 13, 11 am-5pm. Six wonderful gardens are included in this years' tour. Be sure to jot down any ideas or plants that you want for your garden. There is no better way to spend a Sunday in July than strolling around someone else's gardens and being inspired by their success!

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