I bought this Coryphantha elephantidens from a local grower who unfortunately waters carelessly from above. Our water is quite hard here in Tucson and it leaves unsightly calcium stains. This cactus would be gorgeous if I could only get it clean. Does anyone know of a product or method that can remove the stains and not hurt the plant?
On a long run it is better to use rainwater if you can. Rainwater is slightly acid and therefore very good for most of the cacti & succulent species. More - it doesn't contain minerals which can build up in the potting mix. But, on the other hand, it may be polluted. An other alternative is to boil the water and to keep it for few days - some of the minerals may precipitate on the bottom of the tank. I don't trust distilled water for general use because of the potential harmful chemicals it may contain (you'll never know!)unless I am preparing it. In this case it's worth using it. But rainwater collected in a not polluted area is best!
You can clean your plant by using a soft brush and a lot of water, but unless you change something in the quality of the water used, it will come back. I wouldn't recommend this method for plants with wooly areoles or axils.
Thanks for your reply. Yes I've thought about rain water and had that suggested to me when I posted the same question on another forum. Unfortunately I live in a very dry area of the U.S. Right now we are in the worst drought recorded in 111 years. It hasn't rained appreciably in 5 months. Also it's winter time here. Not the best time to put your cactus out in the rain even if we got some.
But I think you're on the right track. Need to wash with some sort of clean water. The only thing that dissolves calcium better than water is some sort of acid which I'm sure wouldn't be too good for the plant. I actually tried some lemon juice on a cotton swab but worried that the citric acid might hurt the roots. But it did work somewhat and dissolved away some of it. It was also suggested I try some diluted vinegar but my worries are the same with that.
I'm not sure why you are so suspicious of distilled water. I've always thought it was the purest water you could buy. What other chemicals besides H2O are involved? I've always thought the distillation process leaves the minerals and other impurities behind.
No matter. What I think I need to do is continue to water carelessly from above for awhile but with as pure a water as I can find. Maybe some purified drinking water.
It did work somewhat.I dabbed some on with a cotton swab and immediately rinsed it off. I'll try again. Maybe I needed to be more patient and leave it on longer. Glad to hear it can't hurt the plant.
I have a lot of plants stained like this. If this works I'll have to buy it by the gallon. LOL
Who knows, maybe when they bloom the flowers will have a lemon scent to them
I have a water softening system so I don't have to worry about chemicals in the water and my cacti seem to love it so I'm also a little confused about the distilled water answer
What you see is not always what you get. I watched an interesting TV program one night on a local Los Angeles based supplier of drinking water. They use a reverse osmosis process that produces perfectly filtered water, and then they ADD stuff so it will taste like mountain stream water. No telling what they add to the distilled. I will say that the curator of the local UCR Botanic Garden buys "distilled" water for his orchid collection and swears by it.
I never really thought about it but I can see your point about companies adding stuff to there product.
I believe a while back I heard some distilled waters from here weren't allowed to be sold overseas because of additives.
Thanks for pointing that factor out.
I have one of them also with about 12 heads on it. Maybe we got them from the same place. I got mine from Bach's a year and half ago. I guess mine has some water marks on it but not too bad. I seem to have problems with that on a lot of the Melocacti I have gotten around Tucson. I'm glad to hear that Daiv's suggestion worked I'll keep that in mind. Be careful with the watering though they are notorious for rotting. I've kept mine pretty dry this winter. Mine's gotten reddened a lot since I moved here. I think I gave it too much sun too soon. At least these guys get red or purple as opposed to some plants that just burn to white which generally doesn't heal for many years if at all.
I got mine at B & B Cactus Farm. It was right out in the sun and I plan to plant it in the yard where it gets good sun. I liked the purple color on the old growth. One thing I also liked about the plant is that it has a lot of little offsets up high on the plant where they'll be easy to take. Haven't had time to give it it's lemon juice treatment. I'll post another pic once thats done.
