Page 1 of 1

Basic soil mix? (also question on feeding cacti.)

Posted: Mon Mar 26, 2012 6:25 pm
by joeyboy11223
Hey guys, I'm going to buy a few cacti online this spring and I was wondering what a good general mixture is that I can use for most commonly available species?

I'm in the UK, shops near me would be Wilkinsons and B&Q.

Would a mixture of perlite, sphagnum peat moss, coconut coir and generic potting soil in some sort of ratio be okay as I already have that stuff lying around? Also I've read mixing in some bone meal is a good idea, when I'm starting out in 3" pots, how much bone meal are we talking?

Finally I've read that liquid tomato feed can be an adequate fertiliser for cacti? I'm a little confused about how often it is necessary to feed cacti during their active period (spring and summer)?

any advice would be super! :D

Re: Basic soil mix? (also question on feeding cacti.)

Posted: Mon Mar 26, 2012 7:12 pm
by iann
John Innes (#1 is good), plus grit, pumice, perlite, or my recommendation is Tesco Low Dust cat litter. I use about 2 parts JI, 2 parts cat litter, and one part alpine grit for most cacti. Perlite does the job but it is a nightmare and will float to the top of the soil, and then either blow away or turn green. Pumice is better than permite but hard to find in the UK.

Bone meal is unnecessary. JI contains all the fertiliser you need for a few months, even for a year or two with slow-growing cacti. After that you can use a soluble fertiliser, or repot. Tomato feed is OK, but use it at 1/4 of the strength on the label.

Re: Basic soil mix? (also question on feeding cacti.)

Posted: Tue Mar 27, 2012 6:37 pm
by joeyboy11223
Cheers for the info Iann. So is the Low dust cat litter is a substitute for perlite in your mix? or is the alpine grit the perlite substitute? I assume the former?

When it comes to alpine grit it seems most places sell it in very big bulk sacks, far too much for my needs. Do you happen to know if chicken grit would be an appropriate substitution for that as I can get my hands on it quite easily.

Re: Basic soil mix? (also question on feeding cacti.)

Posted: Tue Mar 27, 2012 7:03 pm
by iann
This might be helpful. I use it instead of perlite. It holds more water than perlite, is slightly heavier, and is a more natural-looking colour. You can't tell from the picture but it is extremely porous and only slightly heavier than water.
litter5.jpg
litter5.jpg (46.73 KiB) Viewed 1448 times
litter2.jpg
litter2.jpg (81.23 KiB) Viewed 1448 times
You don't have to use grit, but just soil and cat litter is very lightweight and loose so I add a little grit to hold everything in place. Chicken grit is OK if it is not for layers. Grit for layers has limestone or oyster shell in it and many cacti won't like that. Turkey grit might also be better if the chick grit is too fine. Places like B&Q sell small packets of alpine grits, although at about half the price for a tenth of the quantity ...

Re: Basic soil mix? (also question on feeding cacti.)

Posted: Tue Mar 27, 2012 9:56 pm
by joeyboy11223
Thanks for that, I'll pop in to Tesco tomorrow and get a bag. Instead of using grit, could I use sand thinking about it? I know some mixtures use sand. Otherwise there's aquarium gravel..though I don't know if the sizes of the gravel might be a bit big...

http://www.wilkinsonplus.com/aquariums+ ... tZhg%3D%3D

Re: Basic soil mix? (also question on feeding cacti.)

Posted: Thu Mar 29, 2012 9:35 am
by cactihunter
Having read lots of responses to similar questions, I believe sand is likely to block up all of the gaps in the mix that you are trying to add with the litter. The soil mix needs to be really free draining, allow enough (but not too much) water to get to the plant and make the pot heavy enough to balance out the weight of the plant (especially for columnars which are into skydiving)...Homebase do a big bag of Westlands Potting Grit, which is about the same size as the low dust litter and is about £4 for a 20kg bag. Yes its a big bag but it can sit for ages if you do only have a few plants but if you are looking at good mixes and worrying about the size of the grit, I would give you 6 months to over 50 plants minimum :lol:

Re: Basic soil mix? (also question on feeding cacti.)

Posted: Thu Mar 29, 2012 1:53 pm
by iann
No sand.

Re: Basic soil mix? (also question on feeding cacti.)

Posted: Sat Mar 31, 2012 7:01 pm
by philwilliams
Iann- what is the cat litter made of ?

Re: Basic soil mix? (also question on feeding cacti.)

Posted: Sat Mar 31, 2012 7:33 pm
by iann
philwilliams wrote:Iann- what is the cat litter made of ?
Calcined Moler clay. Moler is about 40% clay and the rest is diatomaceous earth.

Re: Basic soil mix? (also question on feeding cacti.)

Posted: Sun Apr 01, 2012 11:13 am
by philwilliams
so is moler clay similar to attapulgite clay ?

Re: Basic soil mix? (also question on feeding cacti.)

Posted: Mon Apr 02, 2012 8:41 pm
by iann
philwilliams wrote:so is moler clay similar to attapulgite clay ?
Not really, but if you find some that is fired hard enough not to crumble in water then you can use it. A good clue is that it turns slightly pinkish when it is fired at a high enough temperature.

Re: Basic soil mix? (also question on feeding cacti.)

Posted: Mon Apr 02, 2012 11:05 pm
by philwilliams
thanks for the info Iann