IN THE GARDEN: Early cold snap affected regular leaf loss — hopefully without permanent damage

Q: I woke up this morning to the plant in the attached picture. I've never had my hydrangeas do this. Is this normal after a few nights of cold? I don't recall them looking like this last winter. Please let me know. I'm heartbroken. I love my hydrangeas. I'm in Little Rock if that helps with anything. I read your article every week in the paper and am always looking forward to learning something. You are always a huge help.

A: Hydrangeas are deciduous plants, so they normally shed their leaves gradually, usually starting before a hard freeze, and then finishing after one. Cold weather hit early this year, and many plants had not started hardening off to enter dormancy yet. Leaves normally form an abscission layer where they attach to the tree, and that helps them fall off. If they are pushed into dormancy earlier than planned, sometimes some leaves will persist well into winter. Hopefully, they will begin to shed and there will be no damage next spring. We often see more damage when plants begin to break dormancy in the spring and then a late freeze hits.

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Q: I saw this multi-stemmed (trunk?) plant on the bottomland of the Van Winkle Hollow Trail this week just before the freezing weather set in. There was only the one plant like it. My photos are blurred, but if you recognize what it is I would love to know.

A: The plant in question is commonly called a wahoo — Euonymus atropurpureus. The deciduous plants have tiny, whitish green blooms in the summer followed by pink fruits that pop open to show the red seeds inside. It is closely related to Euonymus americanus, commonly called hearts-a-bursting or strawberry euonymus; but that one has a wartier fruit, versus the smooth, pink fruit on the wahoo.

Q: I love my ginkgo. I have noticed ginkgoes all over Little Rock are brilliant yellow, and yet for several years, my ginkgo leaves remain green until they fall. Can you tell me why?

A: While it is true that most ginkgo trees have great yellow fall color, not all trees will have the same color, and the type of fall we have will also determine how much color we see. During the growing season, the natural pigments of the tree are masked by chlorophyll, which gives them their green color. If we have warm days and cool nights, and a gradual cooling off process coupled with ample soil moisture, the trees will usually have the best fall color. If we have an early cold snap, which we did this year, it can prevent the fall color from developing as well. Ginkgo trees also form an abscission layer, which makes them drop their leaves. Typically, with ginkgo trees, this occurs rapidly with the trees having leaves one day and none the next. This year, I have noticed a more gradual shed among the ginkgoes, and some are more yellow than others. There isn't much you can do to change the color, or change the weather, so enjoy whatever color you get this year and hope for better next fall.

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Q: When you gave your talk in Harrison a few weeks ago, I heard you mention you have a phone app that lets you monitor rain on your lawn and control your sprinkler system remotely. I didn't get a chance to ask you more about that. Could you please give me some information on what you use and how it works? Thank you.

A: I am somewhat obsessed by the weather and do keep track of what is happening. Instead of setting my sprinkler system on a schedule, I water as needed based on weather conditions in my yard. I have two apps that I rely on to decide when to water. I have a Tempest weather station, which tells me the temperature and the amount of rainfall I get. Then, if I think I need to water, I have my sprinkler system set up with a B-hyve control panel, which I can operate via my phone, even when I am out of town. I can decide which stations to turn on and for how long. Companies do make soil-moisture probes that you can hook up to your sprinkler system so it operates automatically, but my system is old, and soil types vary by zones in my yard, so I make the decisions.

Retired after 38 years with the University of Arkansas Cooperative Extension Service, Janet Carson ranks among Arkansas' best known horticulture experts. Her blog is at Write to her at P.O. Box 2221, Little Rock, AR 72203 or email