If you live in a cold damp zone, with high humidity, clay is a good choice, it dries out faster, use more shallow pots, lots of gravel and sand in the mix and you will do well. Do not use Peat Moss in your mix. Norma

Many cacti have wide shallow roots, but many have a long taproot which can be much larger than the above ground body. Look at your roots and pick a pot based on that. Taproots need a deep pot, short roots need a shallow pot, wide spreading roots can be placed in a shallow pot (ideally a wide one) or a deep one.

The reason for "underpotting" is that (desert) cacti generally don't like their roots to stay wet for too long. If you have a lot more soil than roots, that soil will stay wet and your plant may rot. Clay is a great saver of overpotted plants because it allows soil to dry by evaporation far faster than plastic (sometimes too fast!). Some cacti will flower better when underpotted. Another reason is just to save space, most people have more plants than space. If you don't, you soon will :)

To a certain extent, I find that using larger pots with a more gritty soil is effective when you have the space, plants develop larger root systems, grow faster, and are more resistant to extreme conditions. The soil can retain moisture for a little longer without ever being wet enough to cause rot. Larger pots work expecially well for larger globulars and columnar cacti which will grow into the root space. Taprooted species should generally be left in cramped conditions, even to the point where they break the pot, they will never develop an extensive fine root system to fill a large pot. Another approach is to use a quite heavy soil, but to water very infrequently, effective for many taprooted species which have weak root systems and need really wet soil to get a good drink, but also need the taproot to be dry most of the time. All getting a bit advanced maybe, but things to think about in the future.

Bowl plantings are another acquired skill. Start with tolerant species, and preferably not plants which have wildly differing requirements. Also avoid monsters which will swamp the others before the summer is out. One technique which allows you to ignore nearly all the rules is just to sink individual pots into some kind of substrate in your bowl and cover the whole lot with grit.

shrubs-n-bulbs just gave about as good advice as is possible

Yes, I DO believe shrubs-n-bulbs gave a great answer! I have one more question. I've also been told that I need to make sure to pick plants that have the same growing/dormant seasons. Of course that makes sense but how do you know what season it is for any given cactus or succulent? I have just recently become bitten by this bug and have purchased MANY cacti & succulents that have no names. I have identified a few and a few DID come with names but I don't know how to find what their dormant or growing season are. I've purchased a few books but none list growing seasons.

I realize the most logical answer is to wait and watch their growth patters but I'd love to put together a group planting now rather than wait another 6 months. Below is what I know or am pretty sure what they are.

Genus Species
Agave leopoldii
Anacampseros rufescens
Cereus peruvianus monstrose 'Petra'
Dolichothele surculosa
Echinocereus triglochidiatus
Ferocactus pilosus
Ferocactus chrysancanthus
Glottiphyllum oligocarpum
Haworthia attenuata v. perveridis
Haworthia retusa
Kalanchoe rhombifolia
Mammillaria melancentra
Mammillaria decipiens ssp camptotricha
Matucana madisoniorum
Notocactus scopa
Notocactus macroacanthus
Notocactus magnifucus
Opuntia microdasys alba
Pediocactus simpsonii v.minor
Pilocereus azureus
Pleiospilos nelii
Rhombophyllum dolabriform
Sedum rubrotinctum 'Aurora'
Senecio pendulus
Titanopsis calcarea
Trichocereus thelegonus
Veltheimia viridiflora

For starters, all cactus and agave are summer growers. But they can differ widely on light, water and temperature preferences.

Most mesembs in cultivation have a tendency to be summer-dormant but this varies with your particular environment. Those you have listed fall into this category (Glottiphyllum, Pleiospilos, Titanopsis, Rhombophyllum?). In any event, they must not be grown with cactus in the same spot.

Haworthia and Anacampseros also tend to be more active in spring and fall.

I can't comment on the others.

Regardless of what you do, as shrubs said, your best bet would be to keep the individuals in separate pots and bury them together into a larger container underneath gravel or other top-dressing. This gives you infinitely more control and much less to worry about.

The Titanopsis, Glottiphyllum, and Pleiospilos should be active in autumn, as far into winter as you have good light and sensible temperatures (Titanopsis is frost hardy but won't grow when it is frozen!), and for as much of summer as it isn't too hot and humid. Rhombophyllum will grow right through summer but you'll have to keep it watered, it would be a candidate for growing with a cactus.

Watch out for the Pediocactus, it is likely to go dormant in early summer also. All cacti will do this at some temperature but Pediocactus do it at a temperature that you are likely to have in a normal summer. Pediocactus like to grow in late winter and early spring, even when there are still frosts at night. I'm told they will also put on an autumn growth spurt but don't really do it for me.

I was recently at the Huntington Gardens and noticed they grow their plants for sale in tall pots. That being said, many of my C & S are in normally proportioned pots, roughly twice as tall as wide. A few, like Sempervivum, are in shallower pots.

To get proper IDs and growing conditions, I suggest ordering from Mesa Gardens, Miles To Go, or other reputable mailorder supliers. The Mesa Garden website lists cultural info for most of the thousands of species they list. If you will contact me privately, I can give you the names of some other good nurseries.

thank you guys for some very informative answers to Sharon's question. I've recently been bitten by the bug also. My home is most definitly a jungle. lol. and I love it. I would like to expand a bit on something though. I've had some people to tell me, and you know everyone is going to tell you something different,, that a perticular cactus does not like water, ectra ectra, where as i find those same cactus thrive better for me being watered more, or that cactus will root in water rather than rot in water. What will work for one person will not necessarily work for another person.
As for container gardens, I put together in a pot what looks nice. :)) if and when something gets too big, starts to weep or whatnot, I remove it to another garden.
It seems nothing ever stays in the same place in this house because it ( whatever it may be) will always look better in a different room, different pot, in front of the window, or back in the corner.
My biggest problem at this point is naming plant cuttings that i've never seen bloom and this cotton picking ivy geranium. that thing doesn't like dim light but seems to hate bright sunny windows, I can't seem to win with this plant. I refuse to give up either. lol
all in all, i have more luck not trying so hard to do the "right thing" with THIS plant and just do what i like and if and when the plant doesn't like it, then i move it.

thanks again for your wonderfully informative post guys.
miss daisy

I love your philosphy, Miss Daisy. Life is too short to sweat the small stuff. Had someone (more than one actually) on the American Orchid Society forum stress out over people using the wrong pronunciation of an orchid genus and/or species. This is a case where, even if you pronounced it terribly wrong anyone on the planet would know what you were referring to.

Bottom line is the cactus/succulent folk around here seem much more down to earth....pun intended!

Sharon

Sharon, I hate orchid snobs, or any other snob for that matter. Who cares what you want to call a plant, enjoy it for what it is, not for what it's named.

I guess you have to remember for that some people, their plants are a passion. This passion for things that the average person has no interest in is most prevalent with folks who are intimately involved in something beyond an amateur interest. For example, someone going for a PhD knows way more than anyone else and therefore feels the passion. So do for example some "professional" growers.

We are amateurs, "snobs" are on a different plane. Or even plane-t.

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