Our institute presents peat-free seedling growing media

Come early spring, getting hold of an adequate growing medium for seedlings becomes imperative for both professional and amateur farmers. Many use commercial products, while others swear by their own recipes and homemade mixtures. Though there are many commercial potting mixes available on the market, most of them contain fertilizers and therefore, cannot be used in organic production. This makes selecting the right growing medium more of a challenge for organic farmers, who have to consider economic and ecological factors as well; and the costs of purchasing potting media can be substantial.

What makes a good growing medium?

Potting mixes contain both structural and nutritive components. The ideal planting mixture has good water retention yet also allows for drainage, is pH neutral, is biologically active (characterized by the predominance of beneficial microorganisms), has a balanced supply of nutrients, and is free of pests and foreign materials.

What's wrong with peat?

Peat is formed in wetlands. There are two peat varieties; lowland and upland peat, but for horticultural purposes, it is more common to use the latter, due to its superior physical properties. The use of peat has grown exponentially in recent decades, as it is a major component of growing media for seedlings, potted plants, and ornamental plants. Nowadays, most soil mixtures are peat-based, and may be treated with various loosening, pH-equalizing and humidifying additives and fertilizers. Peat mining entails the destruction of a vital natural resource. More and more ecologically conscious companies and farmers around the world seek peat-free alternatives when purchasing potting mixes that provide advantageous physicochemical properties similar to or superior over peat without causing significant damage to the environment.

To find out more: https://www.globalpeatlands.org/

Studies on the use of peat-free growing media

As part of our MNVH project, we carry out studies on the cultivation of healthy organic tomato seedlings in easily accessible media made from locally available ingredients without the use of peat. During the first phase of the experiment, a number of by-products from the timber industry and various agricultural sectors, various combinations of compost and animal manure were tested under controlled conditions, in phytotrons and in greenhouses. At the current stage of the research, mixtures of confirmed origin are first used in unheated foils to grow tomato seedlings, then, at the end of seedling cultivation, our test plants are transplanted for further examination during the whole growing period, under field conditions. One of the most important basic materials of our experiment is composted organic waste from professional composting plants. The growing media used in our research includes ready-to-use, mature composts from five different composting plants in Hungary. These mature composts are used and evaluated separately during seedling periods and subsequent open-field trials as well.

The key factors in circular agriculture, the various types and production methods of compost, and the importance of composting will be described in detail in the following entry.