Ask The Gardener: Unknown invasive, rhododendrons, plant IDs and more

Gardening editor Doug Oster gets asked a lot of questions. A lot. And he doesn’t mind offering gardening advice. But rather than just limiting those answers to the person who asked, we thought it might be a good idea to share that wealth of knowledge with everybody.

There are three ways to send in your questions:

Email askdoug@535mediallc.com
Submit your question on our “Your Garden” section of our site
Send us a message on Facebook.

(The questions may be lightly edited for grammar/clarity/etc.)

invasive

Question 1: Unknown invasive

John: Can you tell me what this weed is and how I can get rid of it? It first appeared in my backyard and garden last summer, and I pulled it out whenever I encountered it. This year it is back with a vengeance! It’s everywhere and some of the strands have grown to 6 feet or more. Anything I can do besides pulling it out again when I see it? I filled up a whole trash can with the stuff.

Doug: That’s catchweed bedstraw, and it’s critical to remove this invasive before the plant flowers and sets seed. Unfortunately, the best way to control it is by pulling. I know that’s not what you wanted to hear. Get out as much as you can now, if it’s an area that can be mulched, do so. Next season get on it early.

Question 2: Rhododendrons

Janet: You’ve become my go-to guy for quick and thorough answers to my gardening questions … many, many thanks. I have noticed that suddenly the blooms on my purple rhodies have shriveled and faded. I don’t recall this happening in the past; is this usual or is it something in the air that is causing the problem? Several other rhodies in gardens near me seem to have the same “wilt.” The two plants in question are in front of the house (northeast exposure). I mention this because a white rhodie in the back of the house does not appear to be affected. Any help you can provide will be most appreciated.

Doug: That’s just what they do when they are done blooming. Every cultivar blooms a little differently. I have one that hasn’t even started blooming and others that are done. The plant puts on buds very soon after flowering, so if you’re thinking about pruning, this is the perfect time.

Question 3: Plant identifications

Mary: Would you please identify this hanging vine and flower for me? I would appreciate it very much.

Doug: The hanging vine is Creeping Jenny, which is easy to find. Never let it escape the pot or you’ll never get rid of it.

I’m not sure about the second flower, I think it’s a type of phlox, but I’ve never seen pretty variegated flowers like that on the plant. Look up phlox and see if you think it’s a match. Readers, anybody know for certain what this one is?

Question 4: Tomato transplants

Elyse: The tomato seeds you gave away at the Pittsburgh Home and Garden Show are up about 3 inches in peat pots. Can I separate them and put them in my raised bed now?

Doug: Sure. Try to make the transition gentle for them. Give them a day in the shade, then another with part sun and then out to the garden.

Question 5: Bug ID

Esther: Can you identify this bug please?

Doug: I had no idea what it was, so I reached out to my friend Bill Johnson, who among other things photographs insects. He let me know that it’s a Spring Fishfly — Chauliodes rasticornis. Nothing to worry about in the garden.

Question 6: Sedum Atlantis

Pricilla: Does anyone know where in Western Pennsylvania you can buy Sedum Atlantis, which earned the Chelsea Flower Show Plant of the Year title? I never saw it before and it’s beautiful. I would love to get some for my flower beds.

Doug: Find a good nursery that can get it for you. It’s out there in the trade. It’s such a specialty item, you’ll have to call around or have it ordered for you. There’s probably a grower up on Lake Erie who has it.