Perlite Alternatives for Soilless Mixes: Pearl Barley, Diatomaceous Earth & GrowIt

Pearl barley, diatomaceous earth, and GrowIt are all potential alternatives to perlite as an amendment for peat based soilless mixes. Wetting down the mix before mixing in the garage can help reduce airborne particles, but it is still a messy task. Bagged expensive soilless mixes may not have enough aeration and clay shards could be an issue if the area gets tilled.

When considering seed germination, Farfard in the green bag is a great option. It has bark fines that make peppers very happy, but the cost is high near many nurseries. Jiffy Mix or ProMix with added perlite works well too, but one needs to remember the ratio of what was used since buying nonmixed products can be costly.

Ultrasorb or something like that can be found at auto parts stores and can be mixed up in the garage and brought inside to sow and grow. Diatomaceous earth should be used carefully as it is quite dusty; wearing a dust mask when mixing up potting mix is recommended. Feed supplement diatomaceous earth should be avoided as it is powdered and thus ALL dust.

For cold garages where seed germination isn't possible, pearl barley might be an ideal solution. Progresso makes a soup with pearl barley which is organic and small white pearls can easily be knocked out of containers. When using Perlite, wetting it down outside on a windy day will help reduce lingering dust.

GrowIt is a product available from hydro stores which can also provide aeration to soilless mixes. It is important to note that clay holds moisture better than other materials such as silt and sand, and it also holds more nutrients - making a good 40-40-20 mix ideal. However, there are still questions about its use and effectiveness which need to be answered before deciding whether or not to use it.