Floral Preservative Calculator

Flower food and water for a set of vases, with the water volume worked out from the vase dimensions.

Vase shape

The option value is the share of a straight cylinder the vase really holds. A bulb vase of the same height and width holds far less water.

Average inside diameter cm

Measured across the middle of the water column, not at the rim of a narrow necked vase.

Depth of water in the vase cm

Two thirds full is usual. Some stems stand in shallow water.

How many vases

Preservative dose g per litre

Flower food is dosed at about 5 to 10 g per litre. Use the figure printed on the pack you bought.

Times the water is changed

Fresh water and a fresh dose every day or two. Three changes covers a four to six day event.

Water one sachet is meant for litres

Most sachets make 500 ml to 1 litre. Set to zero if you buy loose powder by weight.

Weight of one sachet g

Used to check the sachet count against the weighed dose.

Price per sachet

Your own figure.

Spare allowance for spillage and topping up %

Reset

Free calculator by Handcraft worked examples and methodology No account, nothing stored.