What are these nodules growing on my miniature lilac?

Question

Does anyone know what is growing on my miniature lilac? The nodules are all over the stems and first appeared in the late spring. I have tried searching the internet for an answer but the common problems listed for Lilacs don't mention this. The plant is about 5 years old and has been healthy up until this year. It is surviving but hasn't had the show of flowers it usually has. Should I cut it right back, and if so, is now a good time, or should I wait until the spring?

I live in the Midlands region of the UK.

What part of the world are you in, and have you tried scraping or breaking off any of the nodules? I'm wondering about a heavy scale infestation of some variety, but depends where you are... — Bamboo, Oct 18 '15 at 13:32
I'm in the UK (the Midlands). I haven't done anything to it in case i did the wrong thing. — Annie, Oct 18 '15 at 14:43
Is this plant in a pot or in the ground? And have you tried breaking some open to see if there's anything inside, or how they behave when broken open - I'm wondering about root nodules, which wouldn't be hollow inside... — Bamboo, Feb 20 '16 at 12:37
Thanks for comments. The plant is in the ground, it was originally in a pot but got too big, so i planted it in a sunny open position in the garden, where it did well for 12 months. I then moved it to a more sheltered position because my husband wanted to grow vegetables there. Since then it hasn't done so well. I am going to cut it back and try moving it again to a more open position (just waiting for the weather to warm up) as i read somewhere they prefer not to be too enclosed. I will also cut a nodule open to see what (if anything) is inside. — Annie, Mar 08 '16 at 10:00

score 2 · Answer 1 · answered Sep 08 '16 at 19:42

2

I moved the plant in spring back to it's original position (full sun and open ground) and cut all the stems off (which just left a little stump). I fed it every two weeks and watered when needed and after a few weeks new shoots appeared. New leaves appeared not long after and 4 months on the result is a beautiful healthy new bush with no sign of any nodules.

answered Sep 08 '16 at 19:42

ANN COCKBILL

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Hi ANN. This looks like you came back and answered your own question, which would be great, but the system sees you as an unregistered user and doesn't realize you're already registered. To fix that, just go to the "contact us" link at the bottom of the page. It will give you an option to have your accounts merged, and you can just write in that box what happened. One of the cool moderator guys will come along and fix it, and then your question and answer will both have the same name. If I'm wrong and this isn't you, very sorry about that! – Sue Saddest Farewell TGO GL Sep 08 '16 at 23:00
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Hi Ann, by the way, I see you mentioned that you looked for common problems listed for Lilacs and couldn't find anything. Please know that although this plant is sometimes referred to as "California Lilac", it is not a true Lilac at all, rather it's a Caryopteris, more commonly known as "Bluebeard". – Brenn Sep 09 '16 at 14:23

score 1 · Answer 2 · answered Feb 19 '16 at 19:45

They look like nematode galls.

Galls are abnormal plant growths caused by various organisms (insects, mites, nematodes, fungi, bacteria, and viruses).

It could be something similar to root-knot nematodes: Meloidogyne

Root-knot nematodes of the genus Meloidogyne are one of the most economically damaging genera of plant-parasitic nematodes on horticultural and fields crops. M. incognita attacks many vegetables and fruits, including bean, cabbage, cantaloupe, carrot, celery, cucumber, eggplant, okra, onion, pepper, potato, pumpkin, radish, squash, sweet potato, tomato, turnip, watermelon, and many more species. Feeding of the nematode stimulates the development of enlarged nodules (galls) along the roots up to 20 mm in size. When the galls are sliced open, pinhead sized female nematodes can be seen.

What are these nodules growing on my miniature lilac?

2 Answers2