Vermiculite Alternatives
Finely ground pine bark, also called "pine fines," is a principal ingredient
of most potting mixes. As an alternative to vermiculite, pine fines also
offer water-retentive qualities, especially with smaller particle sizes.
Cotton gin waste includes gin leavings, such as stems, leaves and hulls.
Cotton gin compost renders these waste products into a viable alternative to
vermiculite, also because of its ability to increase water-holding qualities
in mixes. Resembling sphagnum peat moss, coir is the finished product of
ground coconut husks. The University of Arkansas Cooperative Extension
Service reports that coir can retain up to nine times its weight in water.

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On 1/28/2022 11:15, Frank H wrote:
> Vermiculite Alternatives
> Finely ground pine bark, also called "pine fines," is a principal
> ingredient
> of most potting mixes. As an alternative to vermiculite, pine fines also
> offer water-retentive qualities, especially with smaller particle sizes.
> Cotton gin waste includes gin leavings, such as stems, leaves and hulls.
> Cotton gin compost renders these waste products into a viable
> alternative to
> vermiculite, also because of its ability to increase water-holding
> qualities
> in mixes. Resembling sphagnum peat moss, coir is the finished product of
> ground coconut husks. The University of Arkansas Cooperative Extension
> Service reports that coir can retain up to nine times its weight in water.

I usually till in a big bag of peat moss.