Nitrogen, a constituent of chlorophyll, is vital for plant growth and influences the yields and quality of horticultural plans (Malekian, et al., 2011). However, low levels of nitrogen in soil limits plant growth and fertilizers are used to overcome this limitation. While nitrogen stimulates plant growth, it is the major nutrient of concern in water pollution; up to 70 percent of nitrogen applied in normal fertilizers is lost to the environment (Malekian, et al., 2011). Scientists search for natural products that improve fertilizer quality and performance but do not pollute the environment.

Natural zeolites have received attention as soil amendments due to physical and chemical properties that make them suitable carriers of plant nutrients. At the same time, their cation exchange capacity and high affinity for ammonia pull excess nitrogen into their honeycomb structure, preventing it from entering water supplies (Malekian, et al., 2011).

Zeolite serves as natural, non-toxic carrier of fertilizers. When applied to gardens at the beginning of a vegetation period, soil and plants benefit from an even fertilizing effect throughout the entire growth period (Rehakova et al., 2004). Zeolite locks essential nutrients and compounds into its honeycomb structure and releases them gradually into the soil and root system of plants.

Just as important as nutrient retention is the hydration and dehydration capacity of zeolite, which improves water balance in the soil (Rehakova et al., 2004). This is particularly important when growing produce that is highly moisture sensitive, particularly vineyard cultures and fruit.

A study by Rehakova et al. (2004) compared the root biomass and growth rate of vegetables and fruit fertilized with zeolite against non-fertilized control samples. The results indicated that zeolite had a significant impact on final biomass and growth rates. For example, the biomass of parsley increased from 487 g per meter (control group) to 1500 g per meter (zeolitic fertilizer). The same rate of biomass increase applied to carrots and onions. Researchers also observed an increase in the harvest of small fruit. Strawberries fertilized with zeolite yielded a harvest that was 70 percent larger than the control group (Rehakova et al., 2004).