aphids on overcrowded sempervivum!

by Pon
(London, UK)

overcrowded sempervivum

overcrowded sempervivum


I'm a novice and just started raising succulents. I've recently acquired a pot of Sempervivum that are quite overcrowded. It's just the beginning of summer (early June) here in London so I'm not sure if it's the wrong/right time to re-pot some of the buds and separate the plant out a bit? And if I should separate/repot, what the best way of going about it would be.

The buds are also infested with what I think are aphids (little white flecks that look like dust, but grow into little green oval shaped bugs that secrete a green liquid when squished). I've tried vigilantly cleaning and squirting the plant with water, and a bit of dish soap, but they survive, and I've spent a lot of time just picking them off but don't know what the best overall pest control solution would be. Help!

Should I start by separating/repotting the plant a bit- will this alleviate some of the aphids (make it less easier for them to procreate/move around?) and then, what next?

Thanks in advance!

p.s.- I've also got one 'doris day' echeveria I think, which has roots growing out of the bottom of the container. Should I repot the whole thing in a larger container, or separate the three buds into different containers (best method to do this without killing the plant?) Sorry for all the questions, but I'm really concerned!

Drought Smart Plants reply:

Hi Pon, don't worry about asking questions - that's what I'm here for!

First off, your Sempervivum - are you trying to grow it indoors? This could be part of the problem as they are a hardy plant, and happier outside in the weather. They need much brighter light that what you can normally provide inside, even in a sunny window.

I would take it out of the pot and separate each crown, as each of these will make a new plant.

Simply pull them apart - they will most likely already have roots. Even if they don't have any roots, they will quickly grow them under the stress of being removed from their mother plant.

You'll get lots - make sure you have lots of friends lined up to give them to, or start making some succulent crafts - I put my extras into a succulent balls, or a succulent mosaic.

Once you get them apart, inspect them, and see which ones are the worst - you may want to discard the really badly infested ones.

The others can be soaked in a mixture of a few drops of dish soap (not detergent) or Safers Insecticidal Soap, or similar, in water.

This will take care of the majority of the pests.

Aphids are particularly attracted to plants under stress, so if you see them, there is work to be done to de-stress your plants.

Once your pieces have soaked for a few minutes (don't leave them too long) allow them to dry overnight (yes, I know, sounds cruel, right?) and then pot them into new potting soil.

For potting soil, use something that does not retain too much moisture. You can even add more drainage material to the soil, such as pumice, small sized lava rock, turkey grit, small gravel or perlite (this is unsightly, and tends to float to the surface, so it's a last resort if you can't find anything else).

For your Echeveria, definitely, repot it; you can do this anytime it's growing. See also how to grow Echeveria for more.

I would separate each crown, and use the same system and soil mix as for your Sempervivum - even though they grow at completely opposite ends of the earth, they still need similar soil.

Echeveria as a species don't like lime in the soil, so don't get carried away and add anything except the drainage material.

See also these pages:

How to Grow Sempervivum

Succulent Care

Succulent Soil

Succulent Plant Propagation

Good luck, and welcome to our addiction!


Wanting to learn more about Succulent Plant Propagation?

Comments for aphids on overcrowded sempervivum!

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Jun 04, 2011
Thanks so much!
by: Pon


Thanks so much for your clear and sound advice! It's really a relief (and glad to know that I can re-pot anytime instead of only spring). The separate-soak and repot regimen sounds like a good way to go. I unfortunately have to grow them indoors for the time being as I'm still a student and have no balcony or normal window with which to hang them out, but they are on an 8th floor window sill which gets lots of light (and I move them around a bit to get the best light) so hopefully that'll do for now.

Again, thanks a million- it's really a relief to get advice from someone with experience. The flower/plant shops in my area seem to all be run by florists who don't know what to do with plants (especially succulents) until they're already on their way to death in a vase.

All best,

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