2.5 lit. HP
Cardinal red flowers, black spotted on upper lobe. Compact truss. Glossy deep green foliage. Mid to late season. 1.3m x 1m
Parentage: R. Noyo Chief x R. Kilimanjaro
Breeder: RC Gordon, New Zealand, reg. 1979
R. Rubicon is one of the best red flowering Rhododendrons, said by some to be the world’s best red. The reason is the plant is tight in all its parts. The flower is a dark red tight truss and the plant has a tight growth form, roundish in shape in the first few years. As the plant matures it becomes near pointed on top near cone shaped.
The number one requirement to grow good Rhododendrons is quality top soil. Avoid clay and sand like soils.
When planting dig a hole wider than seems necessary so the soil will be soft and friable around the root ball. The roots of Rhododendrons are like fine filaments and will struggle in solid hard packed ground. For this reason, Rhododendrons planted in a lawn area may struggle especially in a dry season. After planting water in well to settle in and to remove air pockets. It is a good idea to cover the soil surface around the plant with humis to retain moisture – though do not use lawn clippings.
After planting and one good watering it should not be necessary to do any more watering, except in drought like conditions. Do not water every day, and even worse, several times per day.
Rhododendrons can be susceptible to mites and a few other pests. For best results spray with an insecticide in spring to keep new growth clean and vibrant. An alternative to insecticide is to use summer oil, or even a bit of dish wash liquid well diluted in water. Apply using a sprayer, or even a watering can with a rosette.
After flowering is finished remove dead flower heads to tidy up the plant. While old flower heads will fall off by themselves over time, removing dead heads will improve the appearance.