Reviewed by Specialty Soils Updated August 21, 2026
Start with the production system, then route to the active medium whose physical behavior fits.
Select the production system before the product
Professional growing media are recipes built around physical and chemical behavior. Start with crop, crop stage, container size and height, production duration, irrigation frequency, fertility program, desired air-and-water balance, and indoor, greenhouse, or outdoor conditions.
| Production starting point | Initial product path | Confirm before selecting |
|---|---|---|
| Seed cells or trays | ProEarth Organic Seeding | Cell size, germination stage, moisture management |
| Soil blocks | Organic Blocking | Block formation and irrigation management |
| General greenhouse/container production | Growers Professional | Crop, container, duration, irrigation, fertility |
| High-air system | ProEarth #2 where appropriate | Actual free-draining requirement—not basket shape alone |
| Controlled flowering system | ProEarth #4 where appropriate | Production program—not simply whether a crop flowers |
| Woody, conifer, native outdoor production | BestWest | Container, duration, irrigation, crop response |
| Long-duration perennial, botanical, or bulb production | Miller | Do not route every perennial automatically |
| Intensive high-aeration, frequent-feed program | M&R where appropriate | Experienced irrigation and fertility management |
| Vigorous flowering without an intensive near-hydroponic approach | Wizard’s where its management profile fits | Crop and program requirements |
Selection variables interact
A shallow container can remain proportionally wetter than a tall container filled with the same medium. A frequent irrigation system may require different physical behavior from a less-frequent manual program. A medium for germination may be unsuitable for long-duration production. Fertility and irrigation must be evaluated with the medium rather than after it.
Starting points are not crop rules
BestWest is not only for blueberries. Miller is not automatic for every perennial. ProEarth #2 is not selected merely because a plant sits in a hanging basket, and ProEarth #4 is not selected merely because a crop flowers. M&R remains a specialist professional medium, not a general homeowner upgrade.
When to trial or request review
Trial candidate media when the production risk or ambiguity matters. Use a control, document irrigation and fertility, observe roots and shoots, and allow management optimization after initial characterization. Choose custom formulation only when a real requirement is not adequately met by a standard product.
Continue through the professional decision path
Connect the production question to the appropriate media family, technical support and commercial review.
Sources & references
General horticultural guidance is supported by the following authoritative resources. Specialty Soils product statements and labeled company observations are first-party information.