I usually apply soluble fertilizer to plants in my unheated bulb house now. However, we are having an unusually cold late winter: near freezing every night, and in the 40s F daytime. Many plants are in active growth, if a bit later than usual. Should I apply fertilizer now, or wait until the daytime temperatures are a bit higher? I don't use pelleted fertilizer on the container plants but have some for the garden which is designed to release slowly at cool temperatures, unlike Osmocote-type slow-release fertilizers which need higher soil temperatures than is typical in the Pacific Northwest.