All plants require food for nourishment and good health. Unfortunately, if you have a garden of alpine plants, appropriate fertilizers can seem hard to come by. A basic understanding of the nutritional needs of alpine plants and their native habitat will make alpine plant food selection easier and more productive.
Alpine, or mountain, habitat usually consists of well-drained, slightly alkaline, rocky soils. These gravelly soils are often enriched with well-draining organic matter, such as peat or leaf mold. Because of their porous qualities, alpine soils are often nutritionally poor.
Alpine plants, adapted to their rocky environments, require relatively little nutrition. Therefore, fertilizer should be applied only as needed. Often, the organic matter in soil is sufficient food for alpine plants.
Soils for alpine gardens should be well drained, containing large amounts of sand and gravel. Most nutrients can be supplied with the addition of well-draining organic matter such as leaf mold, compost or finely shredded bark, which release moderate nutrition over long periods of time.
Apply commercial fertilizer to good alpine soils when plants show reduced vigor or yellowing. Specific formulas for alpine plants are not widely available. An all-purpose, balanced fertilizer (10-10-10, for instance) can be applied at half the recommended strength. It is better to under-fertilize than over-fertilize alpine plants, as another application can be made later in the season.
Yellowing alpine plants are often the victims of overwatering. Before feeding yellowing plants, make sure the soil is sufficiently well drained. If the soil remains damp more than a day after a rain, dig gravel, sand or finely shredded bark into the soil to improve drainage. Give the plant a few weeks to recover and green up before assessing further nutritional requirements. Always water alpine plants sparingly.
Plant appropriate selections in your rock, or alpine, garden. Alpine plants include edelweiss, gentian, saxifrage, rose campion, rhododendron and conifers. Good companion plants from lower altitudes include garden standards such as dianthus, coreopsis and lavender.