Re: In-ground Planting Mix

From: Aroideae at aol.com on 2001.07.16 at 19:40:54(7043) dear dan, i am in west central florida, so our climates are very different, but perhaps my experience with greenhouse beds will help some. i did not use the rock layer because our sand drains rapidly. i used peat instead of coir + composted pine bark + perlite + compost from a friend. i dug the beds out to 24 inches and added the mix. it has been about 6 yrs and the soil surface has sunk about 20 inches. of course our heat here and my keeping the greenhouse at 60 deg in the winter, plus heavy irrigation would cause a more rapid breakdown of the medium. i think it's time to dig out my beds and start again. +More lynn I've dug out a modest area inside my greenhouse for an in-ground planting area. After placing a 4 - 5" [10-12 cm] layer of drain rock in the bottom of this pit, I'll be topping up with another 18 - 20" [45-50 cm] worth of planting mix; as the native soil here in the San Francisco area is essentially clay. My intent is to grow a mixed collection of tropicals in this bed. >From Araceae: Amorphophallus, Anchomanes, Anthurium, Alocasia, Dieff., Philo's, etc. etc.; some Heliconia, various Zingiberaceae, Bromeliads, Palms, Cycads... the usual suspects! Does anybody out there have any experience/ words of advice concerning conservatory (in-ground) soil mixes or specific materials to either use or avoid? I'm considering a mix comprised of locally available components which I'm blending at the approximate ratio of - 40% coir (in lieu of peat moss) - 30% red lava gravel (graded 1/4" size [6.5 mm], clean) - 20 % fir bark (also graded 1/4", clean) - 10% horticultural sand My sample of the above looks great- but I'm really concerned what it'll turn into 5 years from now. Especially since my preference is to not dig out the entire bed and replace the contents much before 2010, if at all possible. What do the under-glass botanical gardens do? Anything special used for the beds inside MOBOT's Climatron for example? Thanks, -Dan

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