too much light?

by Kathryn Stewart
(La Mision, Rosarito, Baja California)

Sempervivum 'Royanum'

Sempervivum 'Royanum'

I'm in a Facebook group where someone posted 2 pix of their sempervivum royanum five weeks apart. She said she uses a grow light. The 1st pic shows a small plant with dark green leaves that are red tipped. The 2nd pic shows the plant is much taller with pale green leaves that are much slimmer. Is this sort of growth normal, or has she used too much light? Thank you for your input.

Comments for too much light?

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Nope, not enough
by: Jacki

Sempervivum need a lot of light. They originate high up in alpine regions where the air is a lot thinner than at sea level, so the ultraviolet light is a lot more intense. Grow lights are good for the short term, but the plant has to be right underneath it, which most people don't do - they want to see the plant, after all.

The thinner, stretching leaves are the dead giveaway. This is called 'etiolating' and that's what it means - stretching to reach more light.

There would be almost no case where you could give a Sempervivum too much light.

The other thing is that Sempervivum NEED a cold winter dormancy. They are not good indoor candidates. The plant will never recover its normal shape unless it gets back to its required conditions.

Having said all that, it's totally normal for Sempervivum to change color with the seasons - that's one of the reasons they're so fascinating!

Semps in Africa
by: Neli

I have grown one type of semp for 5 years up to now. We have heavy rain season and not too hot summer. No winter at all.

At first I did not know how to grow them. They were in full sun planted in garden soil he he he. Some of them got rotten under in the rains but came right after the rains. They never grew over 5cm rosettes. Now I planted them in good soil and gave them protection from the midday sun and they have exploded to 20cm rosettes, looking big and healthy.

Now I bought many more varieties from all over the world. So far so good but too soon to tell. I want to keep some under shelter and some in the garden to see how they will do.

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