Plants grown with organic fertilizers are stronger and more capable to fight winter challenges compared to chemically grown plants.
For best winter protection, spray Buds n Bloom 0-22-25 twice during late summer and early fall using 5 ml / litre (1 tsp) and also drench the roots with the solution.
Also apply 15-20 g of Starter Food per shrub or 100 g per sq.metre during late summer. Together the two treatments will provide needed nutrients for winter.