Monthly Archives: October 2012
Overwintering Vegetables for Spring
There are two groups of vegetables that can be successfully overwintered into the spring: root vegetables and very cold hardy leafy greens.
Root vegetables should be planted early enough that they are a mature size for harvest by mid-November. As the ground begins to freeze, the root vegetables can be heavily mulched with straw to keep the soil from freezing. This method can provide an outdoor cold storage for the root vegetables. They can then be dug and used throughout the winter, as long as the soil is not frozen. Row covers can also assist with this goal.
Spinach, kale, some varieties of lettuce, and some specialty greens such as mache and claytonia are very cold tolerant and can be successfully overwintered with a couple layers of row cover. Depending on the winter and the amount of protection given, these vegetables may be harvestable for much of the winter or they may not have harvestable leaves until it is warmer with longer days in early March.
Garden tools can be a significant investment, so we should take care of them before we leave the garden for the winter as well.
Row covers can be as simple as a thin, old sheet. However, for best success a lightweight, spun-bonded polypropylene fabric is recommended. This type of row cover can be found at local garden centers at certain times of year as well as through garden supply catalogs.
Row covers can be laid on the ground right over the plants to be protected or stretched over hoops. Because of frequent wind, it may be preferable to use hoops to prevent excessive rubbing of the row cover on the tops of the plants. As the weather gets colder, multiple layers of row cover can be used to provide a few more degrees of protection.
Row covers should be carefully secured on the edges so that the wind does not blow them off the plants. When using hoops, the tighter the row cover is stretched over the hoops, the better. The edges can be secured with bricks, cement block, heavy timbers, metal pins, or old milk jugs filled with water.
It’s always a good idea to do some garden cleanup and prep for next year in the fall. It makes spring much more enjoyable!
Those of you who have read this blog through multiple seasons know that I tend to take a rather laid-back approach to protecting vegetables when the weather turns cold in the fall. My typical attitude is that summer vegetables (peppers, tomatoes, etc) have probably about run their course by the time we get to a frost, and you might as well let them go. On the other hand, vegetables like lettuce, radishes, carrots, cabbage, etc are quite cold tolerant. They don’t need any protection until it is going to get down into the mid-20s overnight.
Since we are looking at an early frost this weekend, what to do? (I think this is actually the first early frost in the 5 years I’ve been here. The “usual” since I’ve been here is a frost in early November and often not a hard freeze until December.) The reality is that if you cover your plants for Saturday night, you will probably be able to keep them going for at least another couple of weeks. The question then becomes, will you really get much more ripening on the tomatoes, peppers, etc in that time? My guess is probably not, because even though we aren’t expecting another frost, the highs are going to be the 60s and 70s, while the lows are going to be mostly in the 40s. That overnight temperature is going to start pulling the soil temps down quickly and really slow down growth and ripening on those summer vegetables.
I’m planning to head to our community garden plot tomorrow and pick off the remaining tomatoes and peppers and then see what the weather does. However, I still have a bunch of basil and lemongrass that I want to preserve. These semi-tropical and tropical plants can sustain some damage even in the 30s. I am not ready to harvest and deal with them yet, so we are planning to cover the herbs to keep them going. Our favorite way to preserve these herbs is to mince them in a food processor and then freeze them in either water or oil in ice cube trays. I’ll try to put up a post about that process when I get to it.
The Master Gardeners also planted a bunch of garlic in the Demo Garden this week, so I’ll try to get a post up about that process sometime next week.