In order for Rhododendrons to develop successfully in colder climates they need:
- Porous or acidic soil.
- To be planted in an area that receives morning sun with shade in mid to late afternoon (shade tolerant, not shade loving).
- Protection from winter wind (do not plant in open areas unless well protected with burlap screening).
- The hole for planting must be 15 cm deeper than the root ball and 2 to 3 times wider.
- Loosen the soil in the hole (do not remove).
- Make raised bed with 50% Parkwood® 3 in 1 Planting Mix (compost can also be used) and 50% Peat Moss.
- Do not plant deeper than what the plant was in the nursery container.
- Carefully remove the plastic or metal container (if your pot is fibre you need only remove the rim and bottom). If your plant is balled and burlapped (B&B) untie knots and pull burlap back from the stem once the plant is placed.
- Before planting, loosen roots carefully by hand if they are circling soil.
- Ensure soil mixture is compact around the root ball.
- Water thoroughly and fertilize with Parkwood® Flower Plant Food 15-30-15.
- Well drained, yet moist acidic soil with high organic matter.
- Sandy loam with added peat moss is ideal.
- Mulch with shredded bark, cocoa beans or a mixture of peat moss and compost.
- Do not cultivate around plants, remove any weeds by hand.
WATERING & FERTILIZING
- Water only when soil has dried out. Soak thoroughly using a gentle overhead sprinkler or soaker hose on the surface.
- Check moisture levels weekly (more if weather extremely hot).
- Ensure soil is moist before the ground freezes in the fall.
- Fertilize in early spring (as soon as soil warms up and root growth begins).
- Parkwood® All Purpose Plant Food 20-20-20 followed according to the package directions.
- Fertilize again once new growth has matured with Parkwood® Water Soluble Fertilizer Flower Food 15-30-15. This will encourage new bud growth for the following year.
- Iron deficiency can result from high soil pH and can be corrected by acidifying the soil with peat moss for a long term green colour. In short term, plants can be sprayed with Iron Chelate.
- Do not use Aluminum Sulphate to acidify the soil as it leaves build up in the soil and will cause harm to your plants over time.
- Very little pruning is required unless your plant becomes uneven or grows over a walkway. This can be done while plants are in bloom if you would like the cuttings.
- Greater branching can be encouraged by removing the centre bud of the leaf bud clusters in late fall.
- Dead-Heading is the removing of finished flower clusters; doing this will encourage flower production for the following year.
- Use a burlap screen, staking four corners and an opening left at the top to ensure the burlap does not touch the plant.
- Leaves or cut up evergreen boughs can add extra protection around the base of the plant.
- Spray an anti-desiccant such as Wilt-Pruf.
- Deciduous Azaleas add additional colour (yellow and orange).
- Mountain-Laurel (Kalmia) and Pieris add different foliage texture and will flower in any partially shaded area.
- Wintergreen (Gautheria procumbens), Bunchberry (Cornus canadensis) and Twinflower (Linnaea b orealis) are an excellent ground cover for moist acidic soil in shaded areas.
- Hardy Ferns, Primulas, Columbines, Daylilies, and various wildflowers such as Trilliums, Foam-flower, Virginia Bluebell, and Jack-in-the-Pulpit can also add interest and should be planted at the same time so as not to disturb the surface roots of plants after they are established.