Growing San Pedro

[demonik]

I will be adding some San Pedro cuttings to my lil garden very soon .  I have read every grow log/site for SP that I could find but none have info on indoor growing (growing outdoors is not an option).  To avoid shock I do not want to have to repot after the first time of course, so what size pot would be good for a 5-6' cactus? (I know they get quite larger, but that's as big as I will let them get before cutting).  Soil, light, food, watering I've got down, its just the size of the pot that I am stumped on.  So any cacti lovers out there, please HELP.

[DrYRHead]

Cacti roots do not seem to grow that fast compared to most true leafed plants.
Thus, they should do well in about 1 gallon of soil for quite some time.

[demonik]

Thank you.

[Gorlax]

Cacti grow very slowly. If they grew as fast as leaved plants then saguaros would be the red woods of the desert.

[MstryShovel]

my grandfather had a 14 food san pedro in a 1 gallon pot for all of my childhood 14 years that i could remember they never re-potted it

[demonik]

I went ahead and got a 5 gallon pot (the same kind I have for my SD) along with a great soil mixture.  I ordered them on Thursday and they should be here any time between Monday and Wednesday.  I cant wait! 

[spindrifter]

I just planted some San Pedro seeds this evening.

Smaller pots are better than larger ones for cacti, because the roots don't like to sit in wet soil very long, and if the pot is too big, the roots will rot. Clay pots let the mix dry back out quicker than plastic. Cacti like perfect drainage: try a 1:1:1 mixture of perlite, vermiculite and sterilized compost. When in full growth, they like a thorough drenching once a week, rather than a bit of water every day. Most cacti need a 'rest' in winter, where you water only enough to keep them from shriveling and don't fertilize at all. Almost all cacti like full sun.

Happy growing!

[demonik]

Cool, I'll switch to a smaller pot.  The mixture is 1:1:1.  I was goint to fertilize when I potted it.  Is that a no no, or do I just hold off in the winter?  All of the care sheets say its ok to fertilize in the summer, I just want to make sure.  BTW best of luck with you seedlings.

[spindrifter]

Thanks for the words of encouragement, demonik!

If you are starting cuttings, hold the fertilizer for the moment, and just try to keep the mix humid, but not moist. They will use water stored in the cuttings to fuel root growth. Gently check the bases every week to see if roots are starting to poke out. When they appear, increase the water a bit so that the mix doesn't dry out completely. When you start to see fresh new lighter green tissue forming at the plants apex, start fertilizing every few weeks, and allow the mix to dry out completely between waterings. I think mycorrhizae couldn't hurt, either. Growing this plant indoors might be tricky because of it's vertical habit. You'd have to illuminate the plant from all sides, and it likes intense light.

[demonik]

Thank you for the speedy reply.  Just in time too, the cuttings arrived about four hours after my last post.  They are breath taking and vicious (couldn't find my gloves).  I'm waiting for the heel to dry to plant.  I have a grow light that I will hang over it, and when I move I will be keeping it outside. 

[spindrifter]

Oh yeah.. it is critical that the bases be good and dry before you strike the cuttings. The dried tissue (callus) forms a barrier to bacteria and fungi and protects the cuttings from rotting.

BTW, Gorlax's comment about cacti growing slowly is true about many species, but a lot of columnar types like Trichocereus grow pretty rampantly in summer and suck up tons of water.

Post some pics!

[Arcygenical]

How much dry mass would one expect a cactus like San Pedro put out over the summer months?

[demonik]

I don't know about drying, but I've heard that they grow very fast for a cactus.  And yes I will try to post some pics today when I get the chance.  They are, well wow is the only word that comes to mind.

[demonik]

Well you asked for it
I ordered two, one for me and one for my friend.  This is mine.

This is my friend's.

enjoy

[DrYRHead]

How much dry mass would one expect a cactus like San Pedro put out over the summer months?

They only grow a few inches a year, so one would have to have several cacti to get much out of them per  year. As for dry mass, cacti are 90% water. Thus, if one got 1kg of fresh cacti, that would dry out to be about 100g.