Mineral nutrition with calcium and magnesium, designed for fast-growing aroids and tropical plants (Monstera, Anthurium, Philodendron, Alocasia). Supports the development of strong stems, healthy new leaves, and a robust root system.
CalMag Alga is a powdered mineral nutrient supplement with calcium and magnesium that helps support healthy growth, proper development of new leaves, and a strong root system.
It is especially suitable for fast-growing tropical plants and aroids such as Monstera, Anthurium, Philodendron, or Alocasia. These plants produce large leaves, strong petioles, sturdy stems, and an active root system, so during vigorous growth they may have increased requirements for calcium and magnesium.
Calcium is important for building plant cells, proper root function, and healthy development of new plant growth. Magnesium is an essential component of chlorophyll and helps maintain green, photosynthetically active leaves.
CalMag Alga is particularly suitable for plants that grow quickly, are grown under a grow light, are planted in substrates with a high proportion of coco coir, or in very airy mixes. It is also suitable when watering with soft, filtered, rainwater, or water with a low mineral content.
Possible signs of calcium or magnesium deficiency include:
weak or deformed new leaves,
pale new growth,
yellowing between the leaf veins,
weak stems and soft growth,
slow growth despite regular fertilizing,
problems in plants grown in substrates with a high proportion of coco coir,
fast-growing plants that gradually start to show signs of mineral deficiency.
CalMag is worth using primarily when the plant is genuinely lacking calcium or magnesium. It is not a universal solution for every yellowing leaf.
Mixing into the substrate:
Use 30-50 g per 10 l of substrate. Mix thoroughly and evenly into the substrate before planting. Suitable for freshly prepared aroid mixes, coco coir substrates, and standard potting mixes. For small indoor plant pots, we recommend starting with the lower dose.
Watering:
Use 5 g per 1 l of water and mix thoroughly. Water the plant from above through the substrate. When there is an increased need for calcium and magnesium, it can be applied once a week.
Self-watering pots:
Apply the solution from above through the substrate, then replace the water in the reservoir with clean water. Do not pour the powder directly into the reservoir. Applying it through the substrate delivers nutrients to the root zone while helping to reduce residue build-up in the reservoir.
Foliar spray:
Use 5 g per 1 l of water and mix well. Spray the leaves evenly as needed once every 7-10 days. Apply when the lighting is switched off or low. Do not spray plants exposed to direct sunlight or intense light from grow lights.
Surface application:
Use 70-120 g per 1 m² once a month. This application method is primarily suitable for large containers, growing tables, or greenhouse cultivation. For standard indoor plants, application by watering or mixing into the substrate is simpler and easier to control.
CalMag does not need to be added automatically to every watering or to every plant. If you use hard water or a fertilizer that already contains sufficient amounts of calcium and magnesium, additional supplementation may not be necessary.
CalMag Alga is not a complete fertilizer. It primarily supplements calcium and magnesium, but plants still need a balanced supply of other macro- and micronutrients.
Do not sprinkle the powder directly into reservoirs with LECA, Pon, semi-hydro, or hydroponic systems. This is not a pure liquid CalMag designed for hydroponics. The powdered form may leave deposits and make it more difficult to keep the reservoir clean.
Do not add CalMag to moss poles. These mainly serve as support for aerial roots and help maintain suitable humidity. Apply mineral nutrition to the root zone in the pot.
For small houseplants, do not use unnecessarily high doses. An excess of calcium and magnesium can affect the uptake of other nutrients and cause an imbalance.
CalMag is also not a solution for root rot. When dealing with root problems, it is first necessary to remove the cause - for example, improper watering, lack of oxygen, unsuitable substrate, or hygiene issues.
When applying to leaves, do not spray plants in direct sunlight or under intense grow lights. For young and sensitive leaves of Alocasia and Anthurium, we recommend first testing a small amount of spray on part of the plant.
Yellow leaves can have many different causes - for example, pests, natural leaf aging, insufficient light, damaged roots, overwatering, underwatering, low temperatures, or nitrogen deficiency. Before using CalMag, it is therefore advisable to first consider the actual cause of the problem.
Do not store the prepared solution for long periods. Mix only the amount you need and use it fresh.
Leaves that are already damaged usually will not return to their original condition after applying CalMag. Therefore, assess the results mainly on newly emerging leaves and the plant’s further growth.
