CactiGuide.com

Can anyone offer any help with these two plants? It was originally one large, green plant that started turning red last year. I thought it might be an attack of red spider mites so I cut out and rerooted some green stems and binned the rest. Now these have turned red too. Thing is, they seem quite happy and have flowers ready to go, so do I need to worry?
They're kept in a greenhouse with the rest of my collection (Northern England), behind perspex panels in place of glass, to provide shade.

Most of my Echinopsis chamaecereus are outdoor on the ground without any protection from hot summer and cold-wet winter rain. most of them have red stem. They are cold hardy to -8°C. I think it just normal for this species, with extra sun and temperature.

I too have an E. chamaecereus and this has been my experience. I've had the plant for a number of years and it's growing and flowing profusely. No issues with pests... Actually, no cultivation issues of any kind so far. I think the reddish hue is just normal for this species.

Okay, thanks for the responses. If this is normal I''ll stop worrying and enjoy the flowers as they open! Cheers.