Tips for Beginners, Seedling Culture: An Easy Method
Dr. Mark Konrad
Sometimes an amateur is looking for a simple method to grow a limited number of rhododendron seedlings. The following system might fill this need.
1. Flats: These are formed from ¼ inch wire mesh. A convenient size is 7 x 9 x 1 inch. See Figure 1.
Photo by Mark Konrad
2. Medium: Equal parts of Canadian peat and shredded pine bark are screened through ¼ inch wire mesh and combined to form the medium base in the flat. The surface is then lightly coated with milled sphagnum moss. See Figure 1.
3. Sowing the Seeds: 70-80 seeds are scattered over the surface of the medium. Seeds are sown best in October, just after harvesting. When germination occurs (usually within two weeks) the new seedling can be arranged for equal spacing with a toothpick.
4. Care: The flats are placed in a humid atmosphere either on a windowsill or under fluorescent lighting. (A plastic covering may be used to increase humidity).
5. Fertilizer: Surface application of an acid fertilizer is preferred.
6. After Care: The following year the flats are placed outside under a wire mesh screen cover, after preparing the site. See Figure 2. Partially shaded areas are the best sites. Heavy frost should be avoided, but the screens can be covered with plastic sheeting to protect against light frost. The wire mesh protects against animal invasion and falling debris. The screen can be covered with burlap or pine needles for winter protection.
Photo by Mark Konrad
7. Second Year Care: The following year the flats should be emptied and the seedlings planted in smaller groups or lined out.
8. Marking: Plant identification is recorded using a magic marker on plastic knives. These are then stuck in the ground adjacent to the plants.
Summary: An easy method has been described for raising rhododendrons from seed. It helps avoid many of the pitfalls associated with the process.
Dr. Konrad is a member of the Great Lakes Chapter and a frequent contributor to the Journal.