For propagation and water retention.
Another firm favourite with keen gardeners is vermiculite and when you want to retain water then, chose to add vermiculite to your chosen media.
Vermiculite is a natural, sterile soft mica mineral with great water holding and insulation properties. It also offers a high cation exchange capacity, which means it will slowly release nutrients back to your plant which it has absorbed during watering. Using vermiculite can also aid propagation when used as a top layer, as it reduces evaporation and can help ensure the seed case is lost.
Using vermiculite also reduces plant stress in extreme weather conditions due to its insulation properties. Vermiculite is easy and safe to handle, odourless and light weight and simple to use.
PLANT!T Vermiculite can be used for:
Propagation from seed-its retention of water makes it good for sustaining the growth of seeds.
Potting compost for container planting-it retains moisture-protects against adverse weather and aids in re-watering.
Soil conditioning-its excellent water holding capabilities makes it an excellent adition to sandy soils or dried out ground.