Q: How long should I keep watering plants, given the drought? I don’t want to interfere with their natural inclination to go dormant.

A: Watering will not halt or delay dormancy, since that’s dictated mainly by day length and somewhat by temperature trends, but it will help to keep the foliage (for evergreens), any berries, and leaf and flower buds for next year’s growth hydrated enough to avoid winter injury. (“Winterburn” damage, like freezer burn, doesn’t always manifest right away when it happens… sometimes it only appears in spring.)

There is no set cutoff point to stop watering new plants, but for practicality’s sake, you can pause watering when the soil surface freezes or stays frozen for some time, resuming periodic checks during warm spells or thaws. Granted, plants won’t need watering nearly as often as they might have during the growing season, but if we have a dry winter, they still would benefit from regular checking and occasional watering.

How often to water will depend on many factors, but just as you would during summer (as per our Watering Trees and Shrubs web page), feel the soil around 6 inches deep, and when it becomes somewhat dry to the touch at that depth, watering is probably going to benefit the plant.

Q: When lanternflies were abundant on my tree trunks, bees and wasps were all over them, running around and even climbing over them. What are they doing? Are they “farming” them like ants farm aphids?

A: No, bees and wasps don’t have such a relationship with lanternflies, like ants do with aphids and other sap-sucking insects. A bit like keeping a dairy herd, ants can protect aphids from predators in return for honeydew the ants can lap-up, even though, ironically, ants actively prey on other insects as a more direct source of food.

Tree sap contains mostly carbohydrates/sugars and water, with more dilute dissolved nutrients and proteins. For an insect, it’s not super nutritious, so to get enough nourishment, the insects have to ingest a lot of sap, and the excess gets excreted as “honeydew.” If you see any associated black residue, it’s sooty mold, a fungus that grows on the sugar source. That mold might grow on top of leaves or bark covered in honeydew, but it doesn’t infect the plant itself and will go away once the honeydew has weathered off.

The yellowjackets, paper wasps, hornets, and even honey bees are wandering around looking for easy-to-lick spots of honeydew and ignoring the lanternflies themselves.

When lanternflies are prolific, honeydew can fall almost like a sticky drizzle. Fun aside: “manna from heaven” is thought to have been honeydew falling from sap-sucking insects feeding overhead. Especially late in the growing season, nectar-feeding insects take advantage of any sugar source they can find (due to there being fewer flowers and more hungry colony members), hence why wasps tend to be more of a nuisance around picnics compared to early summer. Adult Spotted Lanternflies produce more honeydew than juveniles earlier in the summer, plus they may congregate more as they find mates and start laying eggs, making it easier for multiple bees and wasps to find them.

Fortunately, the bees and wasps aren’t interested in bothering people — just don’t swat at them, because then they can be defensive and sting.

University of Maryland Extension’s Home and Garden Information Center offers free gardening and pest information at extension.umd.edu/hgic. Click “Ask Extension” to send questions and photos.