Unhappy erysimum bowles mauve

The_old_presbytery

I planted an erysimum bowles mauve last year which had a rocky start but now seems to be doing well. I bought 3 more this year and planted them at intervals in the same bed. The 3 new plants flowered at first but now this has happened to all 3 of them. The plant from last year seems to be unaffected so far. Can anyone tell me what's wrong? 

JennyJ

I don't know what would cause the spots but apart from that it looks like they're putting energy into seed production at the expense of leaves. I think the best approach would be to cut off the old flower spikes right down to where the leaves are so that it doesn't put energy into setting seeds, and make sure the soil is nice and moist so that they aren't stressed and can shrug off whatever the issue is.

Lyn

They don’t put energy into seed, they’re sterile, there’s no need to dead head, only for appearances sake,   they need to be done by cuttings. 
I used to grow them every year, treat them like annuals,  they don’t like my acid soil,  they’re a wallflower they prefer alkaline. 

JennyJ

I'm sure there's something in the pods that mine produce if I let them, but it's been a while as I remove the spikes as soon as the flowers are over - maybe I'll leave one to develop in the interest of finding out. Perhaps mine's not the true BM variety although it does look like it.

Plantminded

I think E. Bowles's Mauve is sterile and doesn't produce seed.  The problem could be down to position - they look very close to the wall, with other plants nearby.  They need full sun to do well and the soil needs to be moist to encourage the roots to get established.  I would cut back all the browning foliage, make sure the soil is moist but not waterlogged and see how they fare over the next few weeks.  In autumn, I'd find a more open sunny space for them, but wouldn't transplant now.

Lyn

There are seeds in the pods,  but they’re no good and don’t sap the plant.  You could try sowing some, just for an experiment. 

JennyJ

I should really have twigged that they never self-sow even though lots of other things do. Either way, producing even sterile seeds and their pods must take some energy from the plant, and the pods don't particularly look attractive to me, so dead-heading is the way to go I think.

The_old_presbytery

Thanks for the replies. They are in front of a wall but the garden is south-facing and they get lots of sun. I will try cutting them back and making sure the soil is moist to see whether they improve. 

Buttercupdays

If you bought young plants that had been grown under protection and then planted them straight outside, they may not have been hardened off properly. Young tender leaves would suffer more from sunburn with the weather we've had.