When Can I Plant in The Garden?

This question is asked by so many once the garden center opens each year and the plants become available.

Typically, my answer is first preceded by the questions “What do you want to plant?” and “How much of a risk-taker are you?” ; and then the conversation continues about the weather, “last frost dates”, their “micro-climates”, cool-tolerant plants, and ways to work with the warm/cold spring days and nights. There are options.

Vegetable gardeners can get a head start with planting by using raised beds which will warm earlier in spring, up to 5 degrees warmer than regular garden areas. Cool-season vegetables such as peas, spinach, lettuce, broccoli, cabbage, cauliflower, radishes, and onions can be planted when soil temperatures reach between 45-55 degrees. However, these same plants often deteriorate quickly (bolting or going to seed) when daily temperatures rise to the 80’s, so being able to get started earlier can result in higher yields.  Cool-season vegetable transplants that have become acclimated to the cold temperatures (hardened-off) can be planted before warm-season vegetable plants such as tomatoes, peppers, eggplants, and vine vegetables.

Since we have had such a wide range of temperatures this spring, ( was it just a few weeks ago that temperatures in the 80’s and we were scrambling to find our short-sleeved shirts) and then dealing with this past weekend’s low temperatures in the 20’s, there are some tips to help our early plantings to survive.

Often, gardeners will use seedling protectors such as cloches (French word for glass bell) or floating row covers to help warm the soil around the plants and to protect from the wind and lower nighttime temperatures. One that I have used in the past is a gallon size plastic milk or water container, that has the bottom cut off. I poke a hole in the handle and thread either a small diameter dowel or a wire coat hanger that has been straightened, thru the handle to anchor the bottle to the ground. The cap of the bottle can be removed during the sunny day to avoid heat from building too much and then can be put back on at night to preserve the warmth. Once the plant has grown tall enough, the bottle can be removed, and stored for next year’s use or recycled. Row covers (made of spun plastic) have become more popular recently as they are useful both at the beginning of the growing season and in the fall for temperature control; but also covers can be used during the season for organic pest control. Another protector that can work is using tomato cages wrapped in plastic with the top open. The plastic should be removed once the danger of frosts have passed.

Traditionally, the vegetable garden planting date has always been the original Memorial Day weekend, although we have had cold frosty temperatures into June in years past. However, for all of  those risk-takers, we do have helpful ideas for working with Mother Nature.