From my perspective as a snapdragon, overwintering is not about growth but about survival. I am a tender perennial, which means my genetic code tells me I can live for several years, but I am not equipped to handle deep, sustained freezing. When temperatures drop and daylight wanes, I receive the signal to enter a state of dormancy. My above-ground growth will die back, and this is a natural and expected process. My life force retreats to my crown and root system underground, where it is better insulated from the harsh elements. My sole purpose during this time is to conserve energy and protect these vital parts so that I may regrow when the soil warms and the sun returns in spring.
To give me the best chance, I need your help to prepare before the ground freezes solid. As autumn progresses, please cease fertilizing me. Any new, tender growth you encourage will be highly susceptible to frost damage and will waste my precious energy reserves. Instead, allow my final blooms to fade and go to seed. You can then cut my stems back to about 1-2 inches above the soil line. This is not harmful; it removes material that would otherwise rot under snow or wet leaves and helps prevent fungal diseases from attacking my crown. A layer of well-composted manure or a balanced, slow-release organic fertilizer worked gently into the soil around my base will provide nutrients that my roots can slowly absorb, strengthening me for the long sleep ahead.
The most important thing you can do for me is to provide a thick, protective mulch after the ground has frozen. This timing is crucial. If you cover me too early, you might trap warmth and encourage new growth, or create a damp environment that rots my crown. Please wait until the top inch of soil is hard after a hard frost. Then, pile a generous 4-6 inch layer of a loose, airy material over my resting place. Excellent choices include straw, pine boughs, or shredded leaves. This layer acts as my insulating blanket. It does not necessarily keep me warm, but it keeps the soil temperature consistently cold, preventing the damaging cycle of freeze-thaw-freeze that can heave my roots right out of the ground. It also protects me from harsh, drying winter winds.
As the grip of winter loosens and daytime temperatures become consistently milder, you can begin to help me emerge. Once the threat of a hard freeze has passed, carefully remove the insulating mulch layer. Do this gradually if possible to allow me to acclimate. The sun will begin to warm the soil, signaling to my roots that it is time to awaken. With the protective blanket gone, my new green shoots will easily find their way to the surface. A gentle application of fertilizer at this stage will give me a welcome boost of energy to fuel my rapid spring growth, and I will reward your careful stewardship with a vibrant display of blooms, often earlier than newly planted snapdragons.
