Hi all, not sure I'd classify myself as a "grower" but I do dabble with my blue spruce. I have maybe a thousand I've grown from seed, ranging in size from 3" to 12" now, and still in 5" plugs.

This fall I will transplant about 250 of the largest to 1 gal. pots and see how it goes (and move to 2 gal. next year, once I see how things develop.

I've been researching soil-less container soils. I can buy Pro-Mix or the Sunshine Mix #4 but am concerned that the pH will be a bit high. I understand that in order for a blue spruce to be "blue" (at least for the 50% that have the ability to turn blue from the regular kaibab variety - although I have many "Majestica" that claim 90% will turn blue, and have some (claimed to be) "Misty Blue" which apparently were selected from the best of the Majestica orchard, but are no longer harvested) the pH should be about 5.5 or even less. I think both of the above pre-mixes have pH's greater than this.

One mix I saw called for about 20% perlite, 20% vermiculite, 60% sphagnum peat moss, and 1/2 cup each of bone meal, blood meal, and dolomitic lime per 8 gallons of mix. I suspect that if I were to use this mix for blue spruce, I might eliminate vermiculite and reduce the lime to maybe 2 tablespoons? It looks from this thread that using primarily pine bark fines may be adviseable? I don't know if I'd need any other additives like CRF? I'm hoping to keep costs down. It seems to me that I can mix my own soil for about 1/3rd less cost than pre-mix, unless I'm missing something? I have hundreds++ more blue spruce coming down the pipeline, so cost is important.

Sorry for being so new at this. It was enjoyable planting the seeds (all outdoors, which was a challenge) but now a few years later I want to keep going with this, so am on to the potting stage. Any advise is helpful.