Does anyone know what this white stuff is?

[simontheintrepid]

Hi
Well done on such a useful site. Being a complete beginner I wanted to ask some questions about this fellow from my windowsill cactus garden. Sorry if they're obvious.



I'm not sure why it is producing this white stuff you can see in the picture (I know it's blurry, autofocus obviously isn't all that good on my camera). It's probably some natural process but I don't have a clue.

Also, is there a particular reason it has managed to twist as it grows. That was what endeared me to it in the shop.

Finally, the pot it's in is watertight. I've heard this might be a bad idea as excess moisture can't drain, although I don't intend to water it much at all. Is this a serious concern?

Thanks very much
Si

[Cac Joh]

Hi simontheintrepid. First the plant you have there is a Euphorbia it is a succulent not a cactus still beautiful I've all ways wanted a Euphorbia. It may be Euphorbia Atrispina look at this link http://www.cactiguide.com/forum/viewtopic.php?t=3066
The white stuff might be the poisonus milky white sap. For the other questions i'll let the experts answer them

[templegatejohn]

Hi Simon, I have to honest and say that I cannot see any white marking on your Euphorbia, but they do indeed have a poisonous latex sap that is white and if the body or indeed one of the spines is pierced this will exude for a while. This is not your cue to go rushing to the dust bin with your plant. Normal care with the plant is all that is needed. Do not handle it if you have any open cuts on the hands and do not rub your eyes until you have washed your hands. Euphorbias are beautiful plants and well worth keeping.

The only other likely cause for white marks are mealy bugs. They appear like small cotton wool marks on the plants particularly in hard to get to places. Inside the 'cotton wool' is a small bug. These will damage the plant over time, so if you do see any 'squashology' is as good a way as any to get rid of them. If there are lots of them a spray with a systemic insecticide recommended for mealy bugs is the answer.

Hard water will also leave white markings on any plant, because of the lime content.

The plant will probably have grown naturally with a twist, this frequently happens.

Regarding lack of drainage, that is definitely a no no, you really need to get the plant[s] into a container with a drainage hole. If it is a container that you particularly like that has not got one, make one (but carefully). You will see hundreds of 'bowl' gardens in garden centres and they will not have drainage holes, but then they want you to go back and buy another one when all the plants in your die.

John

[simontheintrepid]

Thanks for the advice. I had thought it likely that a large garden centre would not really keep their plants in good condition. When I move out of my rubbish house and have some room I'll look into sourcing cacti properly.

I knew this one wasn't a cactus but I hoped it wouldn't matter. I don't mean to offend any purists.

One more thing I forgot to ask. Is the 'cactus compost' that garden centres offer actually any good. I know that might seem a dumb question, but is it any beter than using small rocks and regular soil/sand, or is this another con?

Thanks muchly
Si

[templegatejohn]

Simon, not a problem that is why the Forum is here and there are just as many people interested in succulents in general as there are in 'true' cacti.

Regarding the soil from garden centres it is not usually porous enough in content and is an expensive way of buying what you can probably prepare much better and cheaper, evereyone has their own idea of a good mix, but the main thing is that water drains through it quickly cacti hate to have their'feet' wet for any length of time.

There are many specialist cacti nurseries in the UK where you will get much healthier plants and probably better value as well. Just post a message when you need to know.

John