Cotoneasters can handle heavy pruning and will back bud on older wood. Pruning is great on Cotoneaster because we can predict the direction of growth due to the alternating pattern of the leaves.
Cotoneasters thrive in full sun in the High Desert. Allowing 6+ hours of sun would be best. Keeping in mind that morning sun is better than afternoon sun.
Cotoneaster should be fine in our temperature ranges. We shouldn't have to do much for Winter protection.
Fertilize every two weeks in Spring after the flowering phase.
Wiring should be done in Spring. Since Cotoneasters are vigorous growers you should be careful about the wire cutting into the branch or trunk.
Do not let the soil completely dry out. Cotoneasters do not like wet feet, but need to be moist without completely dry soil.
Cotoneasters should not require too much Winter care in the High Desert.
Cotoneasters should be repotted every 2 years unless it is a tree in refinement. If in refinement you can repot every 3 to 4 years. Don't fully bare root your Cotoneaster.
Bonsai are susceptible to the same pests and diseases as common house plants. The best defense is to keep your tree clean and healthy. Keeping the leaves free from dust will allow proper circulation in your tree. If you notice any abnormal leaf drop, stickiness to the foliage, or visible insects, you need to treat the problem promptly. Start by spraying your bonsai with a solution of 1 tsp dish soap to 1 quart tepid water or Neem oil spray and spray till mixture runs off the leaves; Rinse solution off leaves with plain water and repeat every few days as needed.
Taking softwood cutting in early Summer is the best way to propagate Cotoneaster. They are notorious for being easy to propagate.
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