by Bob Harms  email-here

Madrone Berries and Seeds

Collecting madrone seeds from berries is not difficult, but only fresh, ripe, mature berries (between late November & late February) will yield reliable seeds. The berries form in mid spring, soon after blooming, but usually do not mature until late fall, becoming orange to red. The early summer drought of 1998 killed most of our fruits and many of those that survived never fully matured — the former were brown and hard; the latter remained greenish. Although the berries begin to dry into 'raisins' already in January, I have had decent results from seeds collected well into late February. Some older berries fall to the ground; others may remain on the tree until the next winter (and should not be collected).

November berries
November berries (with previous year's hardened, black berries).
Ripe December berries
Ripe December berries.

My advice is to collect fully ripe berries from a nearby madrone during November and December, while the fruit is still juicy.

3 berry views
Fully ripe berries; top, side, bottom views.

The seeds are encased in a 'nutlet' shell, called a pyrene, beneath the fleshy outer layer of the berry.

berry cut to show pyrene, seeds
Left: Berry opened to show the yellow-orange pyrene. Center: the pyrene highlighted. Right: the pyrene extracted.

The pyrene contains 5 compartments, corresponding the 5–celled ovary of the flower. Each cell may contain several seeds, but at most one mature seed per cell seems to be most common. In one rare exception, a very large and ripe berry had 15 seeds. Most seeds are in the 2–3 mm. range. There seems to be considerable color variation; but black seeds are not viable.

berry dissected
A very ripe berry fully opened. It was difficult to separate the fleshy pulp from the pyrene segments. It seems to have contained 15 seeds.

Pyrene dissected (seeds are not all from the same berry).

Pyrene section enlarged.

At first I tediously extracted all and only the seeds for planting - a waste of time. These days I first remove the outer fruity pulp. Then, holding the pyrene in a cup of water, I gently crush it with my fingers, freeing up the seeds. Then I soak and rinse the whole mess in rain water in order to remove any remaining fruit juice, but leaving pyrene fragments. From the final rinse I spoon out the seeds (and other stuff) and water into a loose cedar-mulch medium, and wash them into the medium with rainwater. (I don't otherwise cover the seeds.)