Commercial growers rely heavily on bark mixes, for drainage - the most important consideration - and weight.

I shift quite a bit of my nursery stock, and have good results with a 50:50 mix of Promix potting soil and bark.

The commercial products are weed-free, and drainage is assured.

Brian

Brian,
Does the Promix already contain the bark or is this something that you mix yourself? I am looking at making my own. I thought it would be cheaper than purchasing the bags like I have done in the past for perennials.

Promix is just a brand of good quality commercial grade potting mix. I grab bags of pine bark mulch from our bulk goods. No, this is not a cheap solution. But it is consistent, light weight, weed free, and excellent drainage.

Brian

here is a simple tree and shrub mix from Dr Bert Swanson, retired professor of horticulture (specialization in nursery management) at the University of Minnesota:

5 parts composted wood chips (wood chips which have been composted for a year with fertilizer, in his case, turkey manure, added to the chips)

2 parts peat moss

that is a very simple mix.

a mix used here at the nursery I work at is

5 parts peat
2 parts sand
2 parts topsoil
2 parts bark chips

a lighter version of the above mix (for plants that need more well drained)

5 parts bark
4 parts peat
1 part sand

I agree with Brian - Promix is expensive, but it is really good. The fact that it is weed seed free is important.

good luck to you.

PP

Thanks.
This gives me something to work from. I know what you mean about the "weed free". I purchase organic potting soil by the truckload for my perennials and it is like black gold, however, the weed seeds love it to.

2/3 coarse fir bark, 1 part peat moss, 1 part coarse perlite, 1 part micro-nutrient...Works for me, and been going strong for 15 years.