Dosing plant nutrients: convert ml per litre to your water volume
Feeding schedules often give millilitres per litre. A simple calculation converts that dose to your actual water volume. Learn what to check with A&B nutrients and measuring jugs.
Read the dose correctly
Check the unit: ml/L means millilitres of concentrate per litre of water. It differs from a total quantity for an entire tank. Also check the growth stage and product formulation to which the dose applies.
Use the actual water volume. A tank with a capacity of 50 L does not automatically contain 50 L of water. Its maximum capacity cannot replace a measurement of the contents.
Calculate the quantity
Required millilitres = dose in ml/L × water in L. As an arithmetic example, 2 ml/L in 5 L of water gives 10 ml. For 12 L, the same rule gives 2 × 12 = 24 ml. These examples explain the calculation; they are not product recommendations.
A larger bottle does not change the calculation. Dose according to the schedule and water volume, rather than the size of the container.
Check both components of A&B
If the schedule lists A and B separately, calculate each component individually. For an example of 2 ml A and 2 ml B per litre in 5 L of water, measure 10 ml A and 10 ml B.
Do not assume that every two-part line uses the same ratio. Follow the exact line. Never mix A and B directly as concentrates; add them separately to water and stir between additions.
Choose useful graduations
A jug designed for a large water volume may be awkward for a small dose. Check the scale as well as maximum capacity. A suitable dosing tool can be easier to read accurately for small quantities.
Read the scale at eye level and keep tools clean. Residue from a previous product should not become an unintended part of the next dose.
Check and record the batch
Record the water quantity and every dose. Then check the finished solution within your programme. In mineral feeding, pH and EC support these checks; target values depend on line, stage, medium and water.
Do not compensate for an arithmetic mistake with an arbitrary extra product. Review the notes and quantities before changing the programme.
Choose your next step
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