The Proteaceae family is found in a vast variety of vegetations, from savannas and grassland to heavily overgrown hillsides. They thrive in areas that are prone to periodic veldt fires. Many of the Proteaceae have evolved specialized survival techniques in response to these fires. Their strong root systems and thick bark on some varieties, have given these extraordinary plants the ability survive the heat and smoke generated by fires. In fact, fire and smoke provide the major trigger in the wild for the Protea seeds to start the germination process. Seed can lie dormant for years waiting for the right conditions, usually brought on by wild fires. For these fire-sensitive species, habitat burning is the single most important cue for triggering germination of the dormant seed.
In growing fire-prone floras commercially, particularly those of Mediterranean zones, a solution had to be found to germinate the Proteaceae seed, without burning your growing fields every year. Following the discovery that smoke stimulated germination of this rare South African Proteaceae; the exploration of the benefits of smoke-mediated germination has expanded to different parts of the world and has been applied in nurseries and in rare flora conservation.
It became clear that seed dormancy of Protea seed is broken when 1) the seeds absorb water; 2) the seed are subject to relatively low temperatures; and 3) the seeds have been exposed to smoke. Various methods have been tried; aerosol smoke, smoke dissolved in water and solids (activated clays or sand particles) that have been smoked have all been effective in promoting Proteaceae seed germination. Various chemicals have also been found to break dormancy in the seed, and even soaking the seed in green tea have been reported to trigger germination in some varieties.
At Cape Flower Fields, we use Smoke Primer Disks to aid germination of our Proteaceae seed. These paper disks are impregnated with the chemicals found in bushfire smoke, as well as other components found to help Proteaceae germinate. When you soak seeds in a solution of these chemicals, you recreate conditions similar to the start of the rainy season after a fire. This triggers germination. We use it and supply it in our Protea Seed Starter Packs.
