Answer: You can apply a winterizer fertilizer now. There are several brands on the market and all include the term winterizer on the label. You'll want a fertilizer that is low in nitrogen but high in phosphorous and potassium. Nitrogen encourages green top growth (the first number on the fertilizer label). You don't want to encourage top growth but you do want the phosphorous, which encourages healthy stems and potassium which encourages healthy roots. So, whichever brand is on sale now is the one to purchase and apply.
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