I'm new here and just read that long thread on container drainage and now have some ideas for improvement. I always recycle soil. There is no way I could possibly mix new soil for my entire container garden each spring and expand it. This year I have already bought over 130 40 lb. bags of dirt for the installation of new planters! And that was a lot of work. My big wildflower containers which are 8'x2'x12" deep hadn't been changed in 4 years. In the fall I amend the old soil with compost, get rid of the old plants and rootballs, loosen it up, and plant the seed. For containers that don't have perennials, in the spring I empty them into my dirt mixer (which is one of those large Rubbermaid storage things I found in the alley a bunch of years ago), add some compost and new soil and perlite, mix it up and it's ready to go into a new planter. So far I found Menards to have pretty decent dirt and I've tried dirt from all the places around here. I mix one bag of their cheap topsoil (which is pretty good with very few clayballs) with one bag of potting mix with 1/2 bag of mushroom compost and a coffee can of perlite. It may not be the best soil but it works. I grow wildflowers, veggies, herbs, and only a couple of annuals. Last fall I had a big ficus tree and a 2 year old rosemary that I grew from a seedling die on me after bringing it inside last fall. I now think my soil mixture and lack of drainage had something to do with that. These discussions here have been very helpful and I'm going to experiment using wicks and maybe there are other things I can add to amend the soil to make it better.

I've posted this several times before: In my estimation, the only case to be made for reusing container soils is one of economics, and you'll never find me argue against making that decision. If you can't afford, you can't afford it. That said and setting economics aside, you might decide to reuse soil for reasons other than economical. Perhaps the effort involved with acquiring (or making your own) soil is something you might not wish to go through or be bothered with. In any case, it would be difficult to show that soils in a more advanced state of structural collapse can somehow be preferred to a soil that can be counted on to maintain its structure for the entire growth cycle. So, if the economic aspect is set aside, at some point you must decide that "my used soil is good enough" and that you're willing to accept whatever the results of that decision are. All soils are not created equal. The soils I grow in are usually pine bark based & collapse structurally at a much slower rate that peat based soils, yet I usually choose to turn them into the garden or give them over to a compost pile where they serve a better purpose than as a container soil after a year of service. Some plantings (like woody materials and some perennials) do pretty well the second year in the same bark-based soil, and with careful watering, I'm usually able to get them through a third year w/o root issues. Watering habits are an extremely important part of container gardening. Well structured soils that drain well are much more forgiving and certainly favor success on the part of the more inexperienced gardeners. As soils age, water retention increases and growing becomes increasingly difficult. If your (anyone's) excellence in watering skills allows you to grow in an aging medium, or if your decision that "good enough" is good enough for you, then it's (your decision) is good enough for me, too. The phrases "it works for me" or "I've done it this way for years w/o problems" is often offered up as good reason to continue the status quo, but there's not much substance there. I'm being called away now, but I'll leave with something I offered in reply on a recent thread: "... First, plants really aren't particular about what soil is made of. As long as you're willing to stand over your plant & water every 10 minutes, you can grow most plants perfectly well in a bucket of marbles. Mix a little of the proper fertilizers in the water & you're good to go. The plant has all it needs - water, nutrients, air in the root zone, and something to hold it in place. So, if we can grow in marbles, how can a soil fail? Our growing skills fail us more often than our soils fail. We often lack the experience or knowledge to recognize the shortcomings of our soils and to adjust for them. The lower our experience/knowledge levels are, the more nearly perfect should be the soils we grow in, but this is a catch 22 situation because hidden in the inexperience is the inability to even recognize differences between good and bad soil(s). Container soils fail when their structure fails. When we select soils with components that break down quickly or that are so small they find their way into and clog macro-pores, we begin our growing attempts under a handicap. I see anecdotes about reusing soils, even recommendations to do it all over these forums. I don't argue with the practice, but I (very) rarely do it, even when growing flowery annuals, meant only for a single season. Soils don't break down at an even rate. If you assign a soil a life of two years and imagine that the soil goes from perfect to unusable in that time, it's likely it would be fine for the first year, lose about 25% of its suitability in the first half of the second year, and lose the other 75% in the last half of the second year. This is an approximation & is only meant to illustrate the exponential rate at which soils collapse. Soils that are suitable for only a growing season show a similar rate of decline, but at an accelerated rate. When a used soil is mixed with fresh soil after a growing season, the old soil particles are in or about to begin a period of accelerated decay. I choose to turn them into the garden or they find their way to a compost pile. Unless the reasons are economical, I find it difficult to imagine why anyone would add garden soils to container soils. It destroys aeration and usually causes soils to retain too much water for too long. Sand (unless approaching the size of BB's), has the same effect. I don't use compost in soils because of the negative effect on aeration/drainage. The small amount of micro-nutrients provided by compost can be more efficiently added, organically or inorganically, via other vehicles. To boil this all down, a container soil fails when the inverse relationship between aeration/drainage goes awry. When aeration is reduced, soggy soil is the result, and trouble is in the making." Al

I always re-use any that I can manage to save other wise I just scatter it around in one of the flower beds and often have a couple more plants come up from it. You can add pete or perlite, ect if you want but not necessary. no fertaliser needed. plants will do fine when transplanted early. jim

David - this is written in a conversational tone, even though I disagree with you on a couple of points. First, the reason I don't reuse my potting soil, and I start with a soil that has as its primary fraction, large particles of pine bark, which takes 4-5 times longer than peat to break down, is that I have found it VERY advantageous to keep my focus on aeration. There are actually ways to quantify a good soil and compare it to a lesser soil by examining it's total porosity and air porosity at container capacity. Container capacity is the soils state of water retention after it has been completely saturated and has just stopped draining. You cannot achieve a level of either total porosity OR air porosity at container capacity using broken down particles of peat/compost/coir as the primary fraction of your soil, even with a considerable volume of perlite added. If you are left with nothing but perlite, which doesn't seem like something that would occur as a common scenario in normal cases of soil aging, then we really aren't talking about reusing an old soil; rather, we'd be talking about reusing the old perlite fraction, which is something quite different. So, if you are reusing the old soil as a significant fraction of the current soil, its very likely you're putting yourself at a distinct disadvantage because of the inherent reduction in aeration and probable excess water retention. I'm not pointing out these facts to disparage how you grow, only so we can understand that SAYING a soil drains well (or is well-aerated) doesn't mean it actually does (or is). We KNOW that fine particles hold more water than coarse particles (of the same material) and vine organic particles tend to compact, further reducing aeration and increasing water retention. IF you were to use inexpensive pine bark as the primary fraction of your soil, and add enough of your used soil to arrive at a favorable state of water retention, you would end up with a soil that DOES have favorable total porosity and air porosity at container capacity. If the soil is entirely broken down as you suggest it is, you STILL need to buy something to replace the lost volume, unless you're using compost ..... and then you end up right back where you started - so why not buy inexpensive pine bark instead of another finer ingredient? Something I wrote on another thread about rooting in water: Though roots form readily and often seemingly more quickly on many plants propagated in water, the roots produced are quite different from those produced in a soil-like or highly aerated medium (perlite - screened Turface - calcined DE - seed starting mix, e.g.). Physiologically, you will find these roots to be much more brittle than normal roots due to a much higher percentage of aerenchyma (a tissue with a greater percentage of intercellular air spaces than normal parenchyma). Aerenchyma tissue is filled with airy compartments. It usually forms in already rooted plants as a result of highly selective cell death and dissolution in the root cortex in response to hypoxic conditions in the rhizosphere (root zone). There are 2 types of aerenchymous tissue. One type is formed by cell differentiation and subsequent collapse, and the other type is formed by cell separation without collapse ( as in water-rooted plants). In both cases, the long continuous air spaces allow diffusion of oxygen (and probably ethylene) from shoots to roots that would normally be unavailable to plants with roots growing in hypoxic media. In fresh cuttings placed in water, aerenchymous tissue forms due to the same hypoxic conditions w/o cell death & dissolution. Note too, that under hypoxic (airless - low O2 levels) conditions, ethylene is necessary for aerenchyma to form. This parallels the fact that low oxygen concentrations, as found in water rooting, generally stimulate trees (I'm a tree guy) and other plants to produce ethylene. For a long while it was believed that high levels of ethylene stimulate adventitious root formation, but lots of recent research proves the reverse to be true. Under hypoxic conditions, like submergence in water, ethylene actually slows down adventitious root formation and elongation. If you wish to eventually plant your rooted cuttings in soil, it is probably best not to root them in water because of the frequent difficulty in transplanting them to soil. The brittle "water-formed" roots often break during transplant & those that don't break are very poor at water absorption and often die. The effect is equivalent to beginning the cutting process over again with a cutting in which vitality has likely been reduced. If you do a side by side comparison of cuttings rooted in water & cuttings rooted in soil, the cuttings in soil will always (for an extremely high percentage of plants) have a leg up in development on those moved from water to a soil medium for the reasons outlined above. Al