Ricker

I would add 2 tsp of dolomitic )garden) lime to each gallon of soil, or 1/32 cup per cubic foot.

The main issue to deal with is increasing water retention as the old soil breaks down into smaller particles. This doesn't occur at an even rate - the older the soil the faster the particles break down into sizes that more rapidly increase water retention.

If you decide to reuse it anyway, let me know. There is a thread that is aimed specifically at how to deal with soils that retain a lot of water. You'll prolly find some helpful tips in it.

Best luck -

Al

I would agree with Al. you want to keep your SWC soil-less mix "Soil-less"! Adding manure screws that all up.

Aeration is a key ingredient to success in a SWC. Getting the perfect balance of aeration, plus upward wicking necessary for the SWC properties to function properly is a challenge.

Here is a telling quote on the Premier (Pro-Mix) website:

"""The process of aeration is one of the most important factors of productivity. Plants absorb oxygen (O2) and release carbon dioxide (CO2) during the respiration process. "Respiring" roots use the sugars made during photosynthesis to provide the energy necessary to drive mineral salt absorption. For most plants, internal transfer of oxygen from the leaves and stems to the roots is too slow to supply enough oxygen to the roots. In order to have good plant growth, the growing media needs to be "aerated", meaning that air exchange between the growing medium and
atmosphere has to provide the plant roots with sufficient oxygen and to remove excess carbon dioxide from the root zone."""

For the dimensions of the 31 gallon EarthTainer, I have found a 3:2:1 ratio of (quality) Potting Mix, Decorative Groundcover Bark, and Perlite together do a pretty good job. This Season, I am doing a full swap-out of the Miracle-Gro Potting Mix combo in all 31 of my EarthTainers, and instead, I am basing my 3:2:1 Grow Media on Sunshine #4 Mix as the primary ingredient.

Where I live, the local Hydroponics Store is selling it at virtually the same cost per cubic foot as Home Depot sells the Miracle-Gro. If I were you, I'd get a bale of Sunshine #4 Mix and blend it in with your old Mix when reloading your SWCs.

Raybo

Ricker.

Al

Ricker.

Sunshine Mix #4 is available EVERYWHERE at all Hydroponics Shops, as it is a staple of those who elect to grow another type of "Cash Crop".

Do some research on the Premier Website on the various Mixes they offer, and what they recommend. Here is a link to their Pro-Mix BRK bark formulation which approximates my 3:2:1 combo Mix. This is tough to find, but it is an interesting "guideline" as to the formulation their Research came up with.

http://www.premierhort.com/website/profweb/aprofweb/premierpress/archi ves/spring00vol7-1/apress7-1e.html

Raybo

Don't know where in CA you are located, but if you are near one of these Hydroponics Shops, you will be able to get the Sunshine #4 Mix at $28.00 per 3.8 cu. ft. bale:

http://www.gardeningunlimited.com/location.php

In fact, the deal gets even better. These stores were holding a "buy an $80.00 Gift Card for $50.00" deal recently. I bought 4 of them. So yesterday when I purchased 3 bales of the Sunshine #4 Mix with the gift card, my actual cost came out to be using the $50.00 gift card, plus $4.00 in cash. Bottom line: $18.00 per bale.

Their on-line store (EHYDROPONICS.COM)is still offering the $80.00 Gift Card for $50.00 through January 31. It can be used in their California storefonts as well - not just for on-line purchases. What a deal if you live near one of their locations!

Raybo