Red Oleander (Nerium oleander) – 10 Seed Count
Oleanders bloom from summer to fall, with fragrant flowers in shades of apricot, copper, pink, lilac, red, purple, salmon, yellow, and white, depending on variety. The plants are best adapted to the west coast, southern states, Florida, and Texas and will withstand dry conditions and wind, as well as salty, marshy soils, making them popular in coastal regions. Oleanders grow 6 to 12 feet tall and wide, and some varieties can be trained to grow into small trees up to 20 feet tall. The flowers are very fragrant. All parts of plant are poisonous to humans and animals if ingested; the plant’s sap can cause skin irritation in some individuals.
1. Gather oleander seeds in autumn after frost or cold nighttime temperatures have caused the seed capsules to split open.
2. Pry open the seed capsule. Remove the fluffy seed mass and place it in a bucket. Position a piece of coarse wire mesh inside the bucket.
3. Gently rub the seeds against the mesh to separate them from the fluffy mass. Pick out the small, light brown seeds.
4. Fill 4-inch nursery pots with a peat-based, soil-less growing mixture. Add water until it feels very moist in the top two inches. Press one oleander seed onto the surface, and cover it with a thin layer of medium-grit perlite.
5. Place the pots inside an unventilated cold frame in full sun. Warm the pots to between 65 and 70 degrees Fahrenheit with a propagation mat or greenhouse warming coil. Do not lower the temperature at night during the germination process.
6. Moisten the growing mixture daily to ensure the oleander seeds never fully dry out. Water with a spray bottle or a garden hose with a misting nozzle. Avoid pouring water into the pots since a strong stream will dislodge the seeds.
7. Watch for germination in two to three weeks. Remove the propagation mat once that happens, and crack open the cold frame to increase air circulation around the oleander seedlings. Water whenever the growing mixture feels barely damp in the top inch.
8. Move the seedlings to a sheltered area outdoors after the last spring frost. Transplant them into 6-inch pots filled with standard potting soil once they grow to 3 inches high. Grow them under light shade and provide one inch of water weekly during their first summer.
9. Transplant the oleanders into a permanent bed in autumn. Choose a sunny site with fast-draining soil. Space multiple shrubs approximately 5 feet apart. Keep them well-watered during their first year in the garden.