CHICAGO — On this edition of Weekend Gardening, Tim Joyce dives right into the mailbag and answers some viewer questions on insects eating rose bush leaves, and how to properly use vinegar to combat pesky weeds.
Viewer email No. 1: Insects eating Cathy’s rose bush leaves
Cathy from DeKalb wrote in that something is eating her rose bush leaves and wants to know if there’s something she can do to prevent it!
Aphids, which are small soft-bodied insects — But usually they feed on roses by piercing the plant and sucking the sugary juices — But curled and brown leaves are likely the result and not seen here.
Thrips — Which are tiny, winged insects but they usually go for rose blooms — Specifically the base of the rose blooms.
So, again probably a miss. Red spider mites also love roses — But often their attacks result in browning leaf curl. So nope.
So that leaves us with caterpillars — Specifically sawfly larvae or also called rose slugs.
These green caterpillars chew on the underside of leaves which creates tan blotches and can skeletonize your leaves. So, I think that’s your likely rose bush-eating fiend.
Luckily, all of these pests have a couple common solutions: spray them off with a strong stream of water from the hose, you can make a mixture of neem oil, water and tiny bit of dishwashing soap and spray the plant — Specifically with the caterpillars — You can pick them off and you can encourage beneficial garden insects and natural predators like parasitic wasps and predatory beetles to control them for you.
It helps to check the underside of your rose bush leaves regularly to make sure you fend off invaders before you have a full-grown invasion and clean up the garden litter below your problem plants so eggs can’t lie dormant over winter and plague you from one season to the next.
Viewer email No. 2: Mary asks, how do I properly mix horticultural vinegar to kill weeds?
Viewer Mary wrote in that she brought horticultural vinegar, which is stronger than kitchen vinegar. She wanted to know the recipe for how to make it into a solution to get rid of some of her weeds, but doesn’t know how to dilute the vinegar.
We’ve gotten a lot of emails on how to kill weeds with vinegar! But the good news is you’ve already got the first part right by buying horticultural vinegar.
Vinegar is pretty watery — So that’s where the cup of salt and ounce of dish soap works to adhere the vinegar mixture to the plants.
You’ll want to transfer the mixture to a clean plastic spray bottle and begin spraying.
You’ll want to focus on the leaves and not the ground.
You might have to repeat this several times every few days over the course of the next couple of weeks. And it’s not a magic potion — So lower your expectation.
This solution works best on most young weeds — For some weeds like dandelions or thistle that have a tap root and are established — You might just need to pull it up.
Viewer email No. 3: Rick offers helpful tip on ivy growing on Chicagoland buildings
Viewer Rick Rose, who said he appreciated the piece on Ivy on buildings from earlier this month, wanted to let us know that because the study was done in a milder climate on newer brick, it may not totally apply to Chicagoland, where a lot brick around here is of an older and softer variety.
Most importantly, the freeze/thaw cycle with moisture come into play here — Which can create and then expand cracks in both our masonry and even road surfaces.
But it was an expensive lesson for Rick in his Rogers Park place — Where north faces of the brick building in the winter don’t get enough sun to dry out during the day so, the retained moisture did cause some considerable havoc on his place.
So, in Rick’s words, take the ivy study with a grain of salt.
If you’ve got any gardening questions, I’d love to hear them! Just email me here at the station with where you live and pictures of your problem plants, at the address below:
TJoyce@wgntv.com