I'm sure other will chime in and with differing opinions but typically it is recommended NOT to include organic matter in a container or potting soil. It is important to understand that growing in containers - and more especially with indoor plants - is a very different set of circumstances than growing a plant in the ground where amending the soil may be appropriate. A containerized plant is more or less a closed system, with limited drainage opportunities and a strong need to maintain aeration and oxygen penetration. This is not achieved with additions of OM, as it will be inclined to continue to decompose and breakdown, slowing drainage and reducing porosity and increasing water retention. None of these will speak to the long term success of any containerized plant :-))

Any concerns you may have about fertility are best addressed by a proper liquid or water soluble fertilizer, not by adding any amendments.

If you look at some good gardening or house plant references you will see that different potting media and different fertilization regimes are recommended for each different kind of house plant. How I deal with it when potting something is that if it belongs to a group with more particular requirements like orchids or cacti and succulents I go to an independent garden center and buy a bagged product labeled for use on these.

I use Happy Frog potting soil with about a quarter to a third part perlite for pretty much all of my non-succulent houseplants and they seem to thrive in that. I do plan on trying out Al's gritty mix for my large fig trees next time I repot, it's highly recommended on this forum but I don't have personal experience with it. I think the number one concern you need to keep in mind when choosing soil is that it is fast draining, most plants can recover from getting too dry but over watering and rot is much harder to come back from. I fertilize with foliage pro.

I reject the whole idea of "amendment" for potting soil. Why start with that which needs amending?

I reject it for garden soil too, and would never add anything to soil but compost, mulch, leaves, other organic material, and only to the surface.

I reject the idea that each plant needs a special soil. I've seen that they all grow deliriously happily in the ground together (unusual plants like epiphytes notwithstanding.) All that is needed is for the roots to have room to grow, and for the soil to contain enough oxygen while moist that roots do not rot when the soil is moist.

Your enemy in this regard is any type of small particles/entity within your potting mix, like vermiculite, which collapses when wet, sand, clay, peat, "moisture control crystals." Get rid of the small particles, avoid those silicone crystals, and your plants can growing like crazy!

Thanks all for your thoughts. I was actually looking at Happy Frog about 2 weeks ago, because I noticed all the good stuff in it. Is the general consensus that something like that with perlite is best?

P.S.: I only add a teenie bit of vermiculite/sand, so no worries. :o)

I think you'd be hard pressed to get a "general consensus" around here lol, but I really like it and it seems to work for me...

I think most would suggest to forget vermiculite and sand...You may want to check out Cacti & Succulents forum for your succulents and here for rest of your plants.

Growing plants in containers is different than growing them in ground...

Agreed. Skip the sand and vermiculite.

Happy Frog is not a highly recommended soil for container gardening by those in the know simply because of the amount of organic matter it contains........it just doesn't hold up well for very long. And I certainly wouldn't recommend it for any cacti or succulents!!

Like Tiffany, I tend not to believe that different plants need different soils with the exception of those like the cacti and succulent that demand very fast, well draining soil. I have found that the bark based mixes discussed in endless detail on the Container Gardening forum - either the 5-1-1 or the gritty mix - will work for ANY plant type with only minor modifications and those are only with the proportions, not the ingredients. And neither contains any organic matter or other standard 'soil amendments' beyond composted bark fines or a small amount of peat.

I'm really taken aback by how everyone feels about sand and vermiculite. The plants I use them for have been doing much better with them. Then again, I add such a small amount it's kind of silly to worry about it.

So it seems bone meal is out, but I've heard nothing but good things about worm castings elsewhere both indoors and out. I'll ask around when I get to the nursery, but I think I'd still like to try the castings. 1 cup to 5 gallons can't do much harm if it's safe enough for AVs.

Bee, I think the problem with vermiculite is that it tends to hold water in the soil, partly because of its shape (lots of smooth surface area) and because it has a tendency to break down when wet and fill pore spaces, keeping water from draining efficiently, also sand seems like it would improve drainage but it doesn't because it it is so much smaller than the other particles in the planting mix that it also fills pore spaces. Perlite, on the other hand, keeps its jagged shape and improves drainage. I would have no problem using a mix with no organic material, its kind of like growing hydroponically but I live in a tiny apartment and don't have the space to mix or store big bags of bark and stone to make the gritty mix so I use a chunky potting soil, like happy frog, and amend it with perlite, I'm sure you would be fine adding some worm castings as well. But maybe you shouldn't be listening to me since I'm obviously not "in the know" lol Like I said, lots of opinions, just make sure your soil is fast draining....

When you use a soil that's so water-retentive you can't water correctly (so you're flushing the soil of accumulating salts when you water) w/o the plant suffering from extended periods of soil saturation, odds are you're going to be leaving a LOT of your plant's potential lying on the table unrealized. Also, if you can't water correctly, making sure your plants are getting what they need, nutritionally, when they need it, is little more than a dream ...... especially if you're depending on soil amendments or the soil proper as a source of nutrients. In the end, focusing on your soil's structure (its ability to consistently provide your plants with a favorable ratio of air and moisture) and ability to maintain that structure is far more important than the soil's ability to feed the plant. With the right fertilizer and a soil you can water correctly, it takes less than 5 minutes to learn how to put in place a nutritional supplementation program that gives you complete control over what plants get, how much, and when they get it. It just doesn't make good sense to use a soil you have to compete with for control over your plants' vitality.

Al

(sand & vermiculite) ..."Then again, I add such a small amount it's kind of silly to worry about it"...

If I may ask: What is the point of adding such small amount of anything?

You also said in your original post that all your plants really like whatever you are growing them in now - if that's the case, why to change?

Just use 50/50 potting soil and perlite if you want to keep is simple. You don't need anything else for the tropicals. The worm castings and other things are better off outdoors than inside your house in a container.

No need to be taken aback by how everyone feels. It's not about how we feel, it's about the fact that sand and vermiculite aren't doing your plants any favors. It's nothing personal about your mix.

Nurseries don't always have all of the knowledge in the world. A lot of people have come here when given absolutely terrible advice by a nursery worker.

long read, but maybe this will help:

http://forums2.gardenweb.com/discussions/2842847/container-soils-water-movement-and-retention?n=8

People get excited about sharing info/concepts that have helped them stop killing plants. I know I do! :)

Alright, thanks all. I'm mulling it all over. Will definitely read through that thread.

Marina,

It's not personal, really. Dave's post above summed it up well, it's about the plants & what does well, ideally best, for them.

Some folks here have been at this for a while, have tried various things & read a lot & shared a lot. Many have learned the hard way & I see most have panned sand & vermiculite for the reasons they've stated.

In ground growing vs. containers are very different things, it's really true. I try & keep things on the simpler side.