In the Prairie Garden® planting concept of Lageschaar Vaste Planten, we use lava granulate. The prairie plants are planted in a top layer of around 8 cm lava rock, type 3/8. The lava that we advise is a specially composed mix of various types of volcanic material from different layers of a quarry. Due to the special blending, the best characteristics of the different layers are combined. This results in the following advantages.
NB: the zero fraction must be minimised, otherwise the ground will still become saturated!
The lava granulate retains the moisture better. It has a water-storage capacity of around 30%, which allows a Prairie Garden® to withstand heavy rainfall and abundant water well. In dry periods, the lava provides the plants with water and prevents dehydration of the ground and plants. A Prairie Garden® is ideal for use in a climate-proof garden.
The lava also reduces maintenance by around 70%. The lava layer forces the plants to root deep. The top layer of the lava dries up, so that weed seeds which blow in have no chance to germinate. This hugely reduces the number of weeds. If no lava is used, it becomes a maintenance-intensive border rather than a low-maintenance border.
Because the plants are planted mixed (in wild context), maintenance without lava requires a lot of professional knowledge. In the spring, the perennials and the weeds grow just as fast. Even for a professional, this can sometimes be a challenge, requiring some plant knowledge.
The following suppliers deliver lava granulate that we can recommend. It has the right colour, granulation and the smallest size fine fraction. Contact them directly for more information.