As the growing season winds down and temperatures drop, it’s time to start preparing your garden for the winter months. Properly “putting your garden to bed” ensures it will be healthy and productive come spring. Winterizing your garden can protect plants, enrich soil, and reduce pests, creating the right conditions for next year’s growth.
Denver’s unique climate, with its high altitude, variable temperatures, and dry conditions, makes winter garden preparation a bit different than in other regions. The key is to protect your soil, perennials, and trees while preparing your beds for the next growing season. Here are five crucial steps to help your garden transition smoothly through Denver’s winter:
1. Clear Out Dead Plants, but Keep Organic Matter
After the first frost, it’s time to remove spent annuals and any diseased plant material. In Denver’s dry climate, diseased plants can overwinter and return the following season, potentially harming your garden’s health. However, don’t just clear everything away. Leaving some organic matter—like small leaves or healthy plant debris—on the ground helps to naturally insulate and enrich the soil. Mulching with organic material can help reduce soil erosion, a common issue in windy, dry Denver winters.
2. Amend and Protect Your Soil
Denver’s soil can be compact and nutrient-deficient, so it’s essential to give it some love before winter. After cleaning up your beds, add compost to improve soil fertility for the coming growing season. As temperatures dip, cover the soil with a thick layer of mulch or straw to insulate it from the freeze-thaw cycles Denver is known for. A good layer of mulch (3-4 inches) will also help retain moisture and protect the soil from erosion caused by the area’s often unpredictable winter winds.
3. Water Perennials and Trees Deeply Before Winter Sets In
Denver has extremely dry winters, so making sure your perennials, trees, and shrubs are well-watered before the ground freezes is critical. Focus on deep watering in late fall. Pay special attention to newly planted trees and shrubs, which may not have developed deep root systems yet. For ongoing care during dry spells, water on warmer days when the soil isn’t frozen, ensuring your plants don’t suffer from winter drought stress.
4. Plant Cover Crops
Consider planting cover crops to improve soil health over winter. Cover crops like winter rye, oats, peas, or vetch help prevent soil erosion, suppress weeds, and add nutrients to the soil. These plants also improve soil structure by adding organic matter as they decompose. In early spring, you can turn the cover crop into the soil, boosting fertility and preparing the bed for planting. Cover crops are a great way to make use of your garden space even when it’s not actively producing food.
5. Plan for Early Spring Planting
Denver gardeners know that early spring can be both a blessing and a challenge. Due to the area’s high altitude, sunlight returns strong as early as February, but temperatures can fluctuate wildly. Take advantage of this by prepping your garden beds in the fall, so they’re ready for early cool-weather crops like spinach, kale, or radishes. You can even set up row covers or low tunnels to extend the season and get a head start on planting while protecting young seedlings from late-spring frost.
