Zeolites are minerals derived from volcanic origin in and consisting of about 50 elements. It contains an array of basic minerals that were spewed back to the earth’s surface in a volcanic eruption, such as silicon, aluminum and other metals. Over millions of years, hot springs leached the calcium, sodium and other contaminants out leaving this unique material. Zeolite, while having many applications, does the following in the garden:
• Improves soil structure, providing better drainage in clay beds
• Increases cation exchange in soil (prevents leaching of nutrients)
• Long lasting, does not break down in soil
Zeolite is considered superior to sand as a soil amendment because while sand also improves drainage, it can decrease water and fertiliser retention. Zeolite’s crystalline structure “grabs” nutrients and water while still providing adequate aeration. Studies have shown that zeolite helps retain nitrogen and increases yields.
Lawn: 20 kg per 100 square metres, apply after aerating.
In garden beds: 20 kg per 10 square metres.
Outdoor planters, beds, or new lawn turf before planting: 1/2″ of zeolite applied to the top of the soil and mixed in.
Bulbs: Mix a handful in with the soil below the bulbs before planting.
Orchids and houseplants: Use zeolite in pebble trays
In a compost pile: Use 1 kg for an average compost pile to aid the decomposition of raw materials, absorb odours from the atmosphere, and improve nutrient retention.
Mulch/Slug Deterrent: lay a ring of zeolite, about a 1/2″ high around hostas or in areas where slugs are known to feed.
Potting Mixes: to improve drainage, mix 1/3 zeolite with 2/3 potting mix.