On 30/07/2014 17:01, Another John wrote:
Hi all

My wallflower seedlings have fairly suddenly acquired small pale
"lesions" all over their leaves. I haven't noticed this in previous
years. Is this due to general distress (for example heat and drought),
or is it a pest?

Pictures are here at Tinypic: (sorry about Tinypic, which now seems to
be wall-to-wall ads and marketing traps -- used to be dead good and
simple!)

http://tinypic.com/r/29dxpp0/8

http://tinypic.com/r/2vllmxl/8

As a supplementary -- someone told me I'm supposed to pinch out
wallflowers ... haven't done this befo should I?

Thanks very much
John




Looks like Flea Beetle damage to me. Not much you can do about it now;
I believe the critters have moved on. I wouldn't want to use an
insecticide on them anyway, as bees love the flowers and may be harmed.
YMMV.
As to pinching out the wallflowers, yes it does improve the plants. By
removing the apical shoot (or meristem), the plant diverts its growth
hormones (auxins) to create new shoots lower down, thus you get a
bushier plant with more flowers. It applies to more than just
wallflowers though. However, if you're growing show Dahlias or
Chrysanths, leave the apical shoot intact so that you get the one large
flower required for the show bench.

--
Spider.
On high ground in SE London
gardening on heavy clay