A lot of people have asked for more information about the use of cold frames for their gardens over the winter. We’ve put together some more in-depth tips below.
During the winter months, watering and maintaining fertility levels of the soil in your cold frame becomes less of a priority or stops completely until around early March. At that time, the sun should be warm enough that you can consider feeding your soil again.
Don’t worry about a snowfall covering your cold frames. Snow acts as insulation for your plants to help prevent winter damage and at this time they will not need any sunlight because of their inactive growing state. You will also find that winter cold frame crops are not bothered with diseases or insect pests like during the summer growing season. However plants that start in the cold frame in an unhealthy state may attract winter aphids when the days start to get warmer.
The colder temperatures of winter will also slow up the evaporation process so you many notice less condensation on the lid of the frame.
For a successful winter harvest and to avoid any fungal diseases, make sure your ventilation and air circulation are adequate for your crops and avoid over-watering. This will promote hardier and healthier plants with less damage to their foliage as the cooler temperatures drop to below freezing.
When temperatures start to climb up the thermometer in March, monitoring moisture is necessary for your seedlings to begin to grow again. Allow the soil to dry between good soakings to encourage solid root growth and work in compost organic matter when it’s time to replant. This will increase water retention to the soil at the same time preventing excess moisture (which encourages disease infestation.)
It’s best not to harvest from your cold frame when temperatures are below freezing inside the frame itself (We suggest a cold frame thermometer to help monitor these fluctuating temperatures and prevent damage to your crops). Placing extra plastic or a blanket over your cold frame will keep your winter crops safe when freezing temperatures don’t allow you to harvest.