Q: What should I do about weevils eating my rhodos?

Dr. Glen Jamieson says:

If weevils are really abundant, weevil larvae can damage the roots while the adult weevils can make the rhodo unsightly.  But for a large rhodo, weevils eating leaves the will not hurt the plant much.  So weevils usually aren’t a big concern except cosmetically.

I don’t recommend using pesticides or using nematodes to eat the larvae in the soil.  In my experience that doesn’t really work well.

Physical removal is your best bet to control weevils: Hand picking the adult beetles after dusk and/or applying a sticky barrier to trunks to catch the adult beetles as they climb up to feed at night or climb down to hide in the day.

You can also put a white sheet under the rhodo after dark, then shake the plant to cause the weevils to drop, and then they can be more easily seen and removed.

Some rhodos are more desirable as food plants for weevils, but rhodos with a tough indumentum like the yakushimanums (yaks) are generally not consumed.

Rhodos near other potential food plants for weevils may have a problem, as the weevils are then more abundant. Weevils have a wide range of host plants including taxus (yew), rhododendron, hemlock, azalea, euonymus, cyclamen, laurel, gardenia, juniper, impatiens, boxwood, holly, grape, strawberry and various other woody and herbaceous plants.

If you can’t solve the problem with weevils eating a specific rhodo and you want to keep it, try moving it to another location and replacing it at the weevil’s location with a less desirable rhodo (at least from a weevil’s perspective), for example, a yak hybrid.

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Please remember:  Gardening is part science, part art, part skill, and a large part luck.  Sometimes even if you do all the “right” things, a plant still won’t thrive.  We offer the best advice we can, but we can’t guarantee that your plant(s) will thrive… or even survive.  MARS assumes no liability for any damage that may occur to your plants, person, or property as a result of or coincidental to our advice.