Cannabis Seed Germination Rate Calculator

Calculate a germination percentage

Enter the number of seeds started and the number that produced a visible, viable germination response according to your chosen recordkeeping standard. The calculator divides germinated seeds by seeds started and multiplies by 100.

Seventeen successful seeds from a group of twenty produces an observed germination rate of 85%.

Define success consistently

Decide whether success means a visible root, emergence from the medium, or establishment of a healthy seedling. Use the same definition when comparing batches. A seed that cracks but fails to establish may be counted differently depending on the purpose of the record.

Why results vary

Seed age, storage conditions, genetics, moisture, temperature, oxygen, handling, and the chosen method can affect results. Small sample sizes can also produce unstable percentages. A single batch should not be treated as a guaranteed prediction for all seeds from the same source.

Record useful context

• Note the batch or source and start date.
• Record temperature and germination method.
• Set a consistent observation window.
• Track seedling establishment separately.

This calculator summarizes observed results. Follow applicable local rules and the seed supplier’s storage and germination guidance.