Growing trial

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Important: clearly delimit the plant beds for each cultivar! Use wooden boards to separate beds and write on the cultivar name of each zone.

Transplant to the same density

and use the same quantity and quality of water and compost for each trial!


if possible with the same regularity after transplantating; as soon as necessary in the first weeks and then approximately every month.

Do not use any products, organic or not,

as the objective here is to see which cultivar is best suited to local conditions.


once only (one final cut).  The objective of the growing trial is to identify which cultivar is best adapted to the growing site for each period of the year and see if the cultivar flowers prematurely, rather than to produce as much herbal tea as possible by regular cutting.


Record cultivar and dates

of sowing and transplanting for each row in a notebook

Note information

on the trial site (sector + landmarks + possible variability factors for each row) and the number of plants in each row.

Carefully observe plant growth

and check each week for pests, disease or other abnormalities.

Determine and record pest attacks

with description and evaluation of the infestation rate (% of affected plants on the plot), impact (evaluation of lost production per affected plant), and mortality rate (% of dead plants).


when half the plants have formed flower buds, all the plants in the row EXCEPT those that have been attacked by pests or disease (ie with estimated 50% or more loss of production or impacted over 50%).

Record height

of the smallest plant (minimum height), the largest plant (maximum height) and the average height (sum of heights of all the plants ÷ number of plants in the row) taking into account only the plants that have not been seriously attacked by pests or disease.

Record date

of cutting (to be done as soon as the flower buds appear on half of the plants in the row, after taking measurements).

If possible, dry each row separately

in order to weigh and note the dry material production per unit (row and zone) and calculate the average dry material produced per plant (taking only into account plants that have not been badly attacked by pests and disease).

IMPORTANT: Do not cut the best plants but leave them to flower for seed collection. (See File Seed Production)