Foliar application of fertilizers provides a way of supplying nutrients directly to plants. All plants absorb nutrients to a limited extent through their leaves and stems, using stomata – little openings similar to the pores of our skin.
Plants absorb foliar fertilizers far more rapidly than soil-applied ones, up to 20 times faster, prompting a quick reaction in the plants.
The purpose of foliar feeding is not to replace soil fertilization. Supplying a plant’s major nutrient needs (nitrogen, phosphorus, potassium) is still most effective and economical via soil application (see adding soil amendments and fertilizers). But the foliar application is an excellent way of supplying plant requirements for secondary nutrients (calcium, magnesium, sulfur) and micronutrients (zinc, manganese, iron, copper, boron, and molybdenum).
Foliar fertilizers help plants compensate for soil deficiencies (soil chemistry imbalance, cold soils, or low soil fertility) during the growing season. Moreover, they help to fortify plants against other types of stress, such as drought, heat, cold, mechanical or insect damage or the onset of disease-susceptible periods.
Application Schedule: Begin your foliar fertilizer applications in early spring. Time the application to encourage and/or enhance critical points in the plant’s growth cycle, i.e. flowering, fruiting, and seed formation. Throughout the growing season, apply to improve nutrient balance as you see fit, during stressful periods and after traumatic events. In the fall, time the application in accordance with the leaf fall.
What you’ll need
- Foliar fertilizer – water-soluble powder or liquid form (see STEP 1. below)
- Spray tank/Backpack sprayer or bottle
- Safety glasses
- Spreader-sticker — optional
- pH meter – optional
- The Holistic Orchard: Tree Fruits and Berries the Biological Way
- Edible Forest Gardens (2 volume set)
- Creating a Forest Garden: Working with Nature to Grow Edible Crops
- Designing and Maintaining Your Edible Landscape Naturally
- The Apple Grower: A Guide for the Organic Orchardist
- The Fruit Gardener’s Bible: A Complete Guide to Growing Fruits and Nuts in the Home Garden
- Curated Youtube Videos on the Subject (note: click the ‘playlist’ button in the top right corner of the video below to browse other videos)