I replied to your thread in the tomato forum and will copy/paste it here. Hopefully someone who knows about the soil conditioner product you have chosen will post as well.

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You have to be careful about the wood. If you are using pine/fir bark you are fine. If you are using part bark, part sapwood you may be looking at a nitrogen immobilization problem as the sapwood ties up N as it breaks down. The reason for using pine bark as the basis of a mix is that is breaks down very slowly (much slower than peat). By using sapwood, the slow decomp is negated and N immobilization can/likely will occur.

In any event, fertilizer is absolutely required in containers as the mix has no real store of nutrients to sustain the plants.

Normally a fertilizer in a 3:1:3 ratio would be good, but if your mix contains sapwood you might choose 3:1:2 instead such as Miracle Grow 24-8-16 to try to offset the N immobilization from the sapwood. It's a bit of a guessing game if your mix contains sapwood as the N tied up by the decomp of the sapwood will be released at some point.

Thanks JaG for your reply!

I will use a diluted fertilizer in 3:1:2 ratio weekly. In addition, should I mix in some Osmocote (CRF) or lime or anything else to the mix?

Also here is a picture of what my OSH redwood soil conditioner looks like: http://i11.photobucket.com/albums/a156/gman68558/PO20080514_0000.jpg [re-using from another post]

Here is a link that might be useful: {{gwi:29531}}

I recall seeing that pic before. Have you grown other plants using this product? If so how did they do?

3:1:2 is a little N heavy for tomatos (3:1:3 would be better for max fruit production, maybe even 3:1:4). My suggesting 3:1:2, such as MG all purpose) is based on the assumption some of the N is tied up by sapwood decomp which I don't know will be a factor.

Yes, you need to add lime. The lime adds calcium, but also brings up the pH of a conifer bark based mix for proper nutrient uptake. Again though, i have no knowledge of the specific product you are using which makes recommendations pretty much impossible.

Products like Osmocote are not needed if you fertilize regularly with a water soluble fert like Foliage Pro or Miracle Grow. They are useful if you forget or can't get to it every week or so.

Pardon me for butting in, but I cd not help it. I need to ask a ? Why use 3:1:3, when MG Tom fert is 18:18:21. Isn't this ratio higher? Wouldn't this be better?
The lime I found out is good, but I thought toms need high K part and low N part. Pardon my lack of knowledge on the subject, but I need to know. I have been using MG Tom fert as above. Am I making a big mistake? My tom plants shot up, but failed half-way. Some toms per plant (5 toms) but lots of mites and whiteflies and brown shrivelled leaves.

Is this bz of MG fert 18:18:21?
Thanks for any replies, esp on the abiove advice to soniagrawal.

18:18:21 for NPK isn't a bad N to K ratio for tomatos. It's a full out silly ratio for P though, for any plant.

If you wish to know why fert makers market higher than needed P fertilizers just read this.

It boils down to making money by giving consumers what they think they need instead of spending money trying to educate them as to what plants actually need.

Your choice of ferts isn't likely to cause any problem though (other than pollution).