Breaking Plumeria Seed Dormancy
For plumeria seeds to come out of dormancy, we have to break their physical dormancy factors. Plumeria seeds have a thick seed coat, The most common method is some form of soaking the seed in warm water. Others use scarifying (scratching the surface) the seed, artificially weakening the outer coat of the seed. Water and warm temperatures are the two factors that break plumeria dormancy.
There are several method used to help test viability and germination of Plumeria seeds: Pre-Soaking in warm water, Soaking between paper towels overnight, soaking between paper towels in a plastic bag, planting directly into soil, placed in Styrofoam and float in water, planting directly into plugs, etc. They all work, the trick is to find out which method or combination of methods work best for you.
Steps of Plumeria Seed Germination
- Imbibition. The seed rapidly takes up water and the seed coat swells and softens. The outer seed coat becomes soft whit water.
- Interim or lag phase. During this phase the seed activates its internal physiology, cells respire, and the seed starts to make proteins and metabolize its stores of food.
- Radicle and root emergence. The cells start to elongate and divide, bringing the root and radicle out of the seed.
To find out whether or not your seed is viable, do a germination test.
Here are two methods:
Drop the seeds in a warm dish of water wait 4 hours or overnight, and count how many seeds absorb water and plump up. The ones that plump up will most likely germinate.
Or wrap the seeds in a wet paper towel, place in a warm spot, wait 4 hours or overnight, and count how many seeds absorb water and plump up. The ones that plump up will most likely germinate.
If you save your seed from the year before, think about this: the life of a plumeria seed can be cut in half by an increase of just 1 percent in seed moisture or by an increase in storage temperature of just a few degrees. A simple rule of thumb is to store your seed in a dry cool place.
A study was done by Eulas Stafford with the Plumeria Society of America. He gathered a large quantity of Slaughter Pink seeds and proceeded to plant 10 seeds a year for 10 years. The results: The first two years 100% germinated and after that an additional 10% failed to germinate each consecutive year. The 10th year only 1 germinated.