Aptus MassBoost: Prevent Calcium & Magnesium Deficiencies for Improved Fruit and Flower Development

MassBoost by Aptus is an organo-mineral plant booster that effectively prevents Calcium (Ca) and Magnesium (Mg) deficiencies, leading to a significant improvement in fruit and flower development. Both Calcium and Magnesium play crucial roles in fruit and floral development, and their deficiency can cause flower drop, poor fruit set, and yield reductions. MassBoost combats these deficiencies by providing the essential minerals in a highly available form, chelated in L-amino acids, ensuring improved absorption and utilisation by the plants.

Features and Benefits

  • Organic Nitrogen, Calcium, and Magnesium: Combination of essential minerals and L-Amino Acids for healthy plant development.
  • 100% Water Soluble: Easy to mix with no residue left behind.
  • High Bioavailability: Ensures efficient absorption and utilization of the provided nutrients.
  • Improved Fruit and Flower Structure: Enhances firmness, structure and overall quality of fruits and flowers.
  • Boosts Plant Performance: Provides an extra boost during critical developmental phases of the plant.

How to Use

  1. Use MassBoost during all stages of plant development, with increased dosage during the flowering phase.
  2. If necessary, use MassBoost at a lower dosage or as a foliar spray.
  3. For reverse osmosis (RO) water and soilless mediums (like coco coir), higher dosages of MassBoost may be required.
  4. When mixing with phosphorus supplements (like PeakBoost), make sure to mix one in the solution before adding the other to minimise formation of calcium-phosphate bonds, which renders both unavailable to the plant.
  5. For foliar feeding, mix FaSilitor first, then add MassBoost, and adjust pH to about 5.8. The L-amino acids in MassBoost act as a surfactant, providing a more effective foliar treatment for nutritional imbalances.

Aqua Gardening Suggests These are Best For

MassBoost is ideal for gardeners and growers of fruiting and flowering plants who are looking to improve flower development, fruit set, and overall yields. It is suitable for use with all growing mediums, including hydroponics, soil, and coco coir. MassBoost is compatible with various watering systems and works well with other Aptus plant fertilisers.

Notes from Aqua Gardening

  • Exercise caution when using MassBoost on young plants, as the nitrates can cause tip burn and stress. If this occurs, use a CaMg supplement without nitrates to buffer RO water.
  • Customise your feeding schedule using the Aptus Nutrient Calculator.
  • Use MassBoost in combination with PeakBoost & FinaleBoost during the last weeks to achieve maximum weight, firmness, and quality.
  • Pay attention when mixing PeakBoost and MassBoost, as they can react together. Always add one, dilute and mix, then the other.
  • MassBoost contains low levels of nitrates that can cause tip burn if fed at too high rates on young or weak plants. Start with a lower dosage and increase based on your plant's response.


What is Aptus MassBoost and its purpose?

A:Aptus MassBoost is an organo-mineral plant booster designed to prevent Calcium and Magnesium deficiencies while stimulating powerful fruit set and development. It provides these minerals in a highly bioavailable form by chelating in L-amino acids, improving the structure and firmness of flowers and fruits.

How is MassBoost used?

A:MassBoost should be used during all stages of plant development, with increased dosage through the flowering phase. It can be applied to the roots in a feed solution or as a foliar treatment for maintenance or to treat deficiencies. When using reverse osmosis (RO) water and soilless mediums, higher dosages may be needed.

Can MassBoost be used with other plant supplements?

A:Yes, MassBoost can be used in combination with other supplements, such as PeakBoost and FinaleBoost, for maximum weight, firmness, and quality. However, caution should be taken when mixing MassBoost with phosphorus supplements to minimise the formation of calcium-phosphate bonds, which can render both unavailable to the plant.

What is the role of L-amino acids in MassBoost?

A:L-amino acids provide organic nitrogen that promotes robust vegetative growth and photosynthesis without the risk of burning or overdose. They also act as a surfactant, making the minerals easily absorbed into the leaf tissue and boosting beneficial bacteria populations.

How do Calcium and Magnesium contribute to plant growth?

A:Calcium is crucial for fruit set and floral development, as well as being involved in cell wall structure, enzymatic activities, and improving the firmness of fruits and flowers. Magnesium is essential for photosynthesis, particularly when combined with L-amino acids. Both minerals help raise the internal plant pH to resist fungal attacks.

Are there any special considerations when using MassBoost on young plants?

A:Take care when using MassBoost on young plants, as the nitrates in the product, along with nitrates from your base fertiliser, can cause tip burn and stress. In such cases, use a CaMg supplement without nitrates to buffer RO water. Start with a lower dosage of MassBoost and gradually increase based on your plant's response.

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(SKU: 130691)

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