Petunia leaves curling/stunted growth

AnnaBruno

I have a problem with my RHS Storm Lavender petunias that have been grown from seed under plant lights, new leaves come out smallish and curling. A third plant does not display these issues. I did have a limited aphid problem, treated with Neudorff aphid pest spray immediately, isolated plants and cut back the affected growth (should be visible where in photos). there is no sign of aphids now (I have examined carefully with magnifying glass). But the new growth comes back stunted and curly. I am at loss at what to do and whether these plants can be saved - would be grateful for any input! Thanks!

JennyJ

I think I would pinch out the tips (good idea anyway, to encourage bushiness) and see how they go. Give them as much daylight as you can. Maybe a feed too, if they're staying in the same pots until they can be planted out (probably 4 weeks or so, maybe less if you're in a mild climate).

Kili

They look to big for those pots there in. There well advanced and should be in the ground if the area/frost date your in allows it I would get them in the ground, basket or whatever it is you intend to put them in now.

Pete.8

Leaf curl can be caused by a chill.
If you leave them by the window overnight that may be the cause.

AnnaBruno

Thank you, Jenny, Kili and Pete! I'll try your advice and pinch, repot with slow release fertiliser and move them back to my plant stand w plant lights under the kitchen counter, where the temperature should be warmer and more even - I was just worried that this might somehow be related to aphids, but if it probably isn't I'll take my chances. For reference, here is a picture of the third plant which has been doing better, but I see that this one also has some slight curling in the new leaves. (And I know I should probably pinch the flowers, but I just didn't have the heart to do it...)

BobTheGardener

Also, pest sprays are usually specific about not being used on very young foliage as it can cause distorted growth this.  I'm not saying that's the cause but is something to be aware of.  Viruses can be transmitted by aphids, too.  The new growth which appears after pinching out the distorted parts is usually unaffected so that's what I would do.

AnnaBruno

I wasn't aware of that, Bob! There's no warning on my spray, but I do remember thinking that the smell was rather harsh (alcohol-y) and hesitated slightly before drenching my poor little petunias... I'll pinch back and see what happens. I hope the spray hasn't affected the roots as well.