Re: Soil mix!!

From: "Clarence Hammer" chammer at cfl.rr.com> on 2002.04.03 at 16:38:17(8435) Susan, I have also heard of 'something' being in pine bark and needles that discourage growth of weeds, so you don't have to move to the funny farm. I've also heard that you should use cypress mulch because pine bark mulch attracts roaches. Also heard they all attract termites. Perhaps faery tales, rumor, grandpa's wood lore, or fact. The idea with a mulch of any kind is that if it's thick enough, as in at least 3 to 4 inches, most weeds will not grow thru it, and it also cuts off light to any seeds that may require it to germinate. Even layers of newspaper, sawdust, etc can be a mulch. Bark in a mix apparently uses up nitrogen as it breaks down, so if it's a large part of the mix, extra nitrogen as fertilizer should be used. I don't like bark 'nuggets' (big 3 to 4 inch pieces) which is widely available here as a mulch. The fine stuff that's left in that bag after the chunks are taken out is what I like. 2 cubic foot bags of it are available here for just a few dollars if one looks long enough. 'Fine' to me is pieces about 1/4 inch and smaller. Another product I like is called 'soil conditioner' here. I think it's fine bark that's been composted but not completely. Lot of 'soil-like' material mixed with small bark. I've only seen it offered at wholesale nursery supply places. +More I do agree perlite has faults---fluoride, and yes, some of it does float to the top of the mix. But given the wide availability of it, and lack of other good substitutes, it's not that bad for most plants. I've experimented with some success with lava rock (1 to 2" pieces) mixed with a peaty bark mix for large philodendrons. But lava rock isn't cheap either. If someone would produce a crushed lava rock in 1/4 inch pieces, I think it would make an outstanding sub for pumice. But I'd probably only use it on succulents. Back in the old days (70s) I used to swear by a soilless mix touted by Elvin MacDonald (wrote books on gesneriads, indoor plants), and I grew perfect plants in it. Lean mix was 1 part peat, 1 part perlite, and 1 part vermiculite. Rich mix was same but with 2 parts peat. At the same time, Cornell University touted a mix that I believe was just peat and vermiculite. I found this too moisture retentive. Knew of a Hoya guru named Loyce Andrews that grew them in pure vermiculite. I rotted everything when I tried it. A relatively new material being used in the agricultural trade called Turface has some possibilities. It's been used for conditioning baseball fields for years apparently, and is a fired clay product about 1/8 inch size. I've found it at wholesale agricultural supply places and an Ace Hardware store, and a feed store under another name. Always looking for a new soil amendment, I'm fascinated with experimentation in potting mixes, especially for my Aroids. Anyone with ideas, experiences, suggestions, would love to hear from you on this forum. Russ.

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