Preheating soil for the spring garden
Some nice info from http://www.waldeneffect.org/
The main difference between planting in early spring as opposed to after the frost-free date is soil temperature — cold ground makes seeds rot before they sprout. Luckily, there are several methods of heating up the soil, ranging from the simple to the complex.
Also as a side note these quick hoops with some minor changes can also be used for a chicken run to put between your rows and allow your chickens to weed your garden for you.
You probably noticed that each of these techniques shares two factors — sun and time. Your soil will naturally warm up as spring advances; you’re just trying to expedite the process so you can jumpstart the garden year. To eat from your garden as soon as possible, combine all three methods and plant seeds as much as three months before your frost-free date.
Even under quick hoops, you won’t want to plant frost-sensitive vegetables like tomatoes and cucumbers anytime soon. However, there is still a wide selection of crops to choose from for your spring garden. I’ve highlighted the easiest ones in the chart below.
|Beets||Seeds||Beet seeds can sometimes be difficult to germinate. As with other root crops, beets need loose, loamy soil.|
|Broccoli||Transplants||The more advanced gardener can start her own seedlings either inside or in a quick hoop. Otherwise, buy sets from the local feed store when night temperatures have risen into the high 20s to low 30s Fahrenheit.|
|Brussels sprouts||Transplants||The more advanced gardener can start her own seedlings either inside or in a quick hoop. Otherwise, buy sets from the local feed store when night temperatures have risen into the high 20s to low 30s Fahrenheit.|
|Cabbage||Transplants||The more advanced gardener can start her own seedlings either inside or in a quick hoop. Otherwise, buy sets from the local feed store when night temperatures have risen into the high 20s to low 30s Fahrenheit.|
|Carrots||Seeds||Well-drained, loamy soil is mandatory. Carrots are slow-growers, so weed carefully to give the seedlings breathing room.|
|Collards||Seeds||Spring greens are some of the easiest vegetables to grow. In addition to collards, spinach, and Swiss chard, consider trying some Asian greens for variety.|
|Leeks||Seeds||Leeks take a long time to grow, so I generally prefer the perennial Egyptian onions instead. As with other root crops, leeks need loose, loamy soil.|
|Lettuce||Seeds||Leaf lettuce is my earliest harvest of the year because I always plant it under quick hoops. You can cut leaves within a month of planting, but be sure to seed a second bed as soon as you start eating the first — lettuce becomes bitter within a few weeks of first harvest.|
|Onions||Seeds, sets, or transplants.||Getting your onions to germinate out in the cold can be a bit tricky, so you may choose to start them inside or under quick hoops to ensure they have time to grow before summer heat stunts them. Select a variety appropriate for your day length (short day in the south and long day in the north.) Many gardeners simplify planting by buying sets (tiny bulbs) from the local feed store, but onions grown from sets usually don’t store well.|
|Parsley||Seeds||Parsley is grown very similarly to carrots, but you pick the leaves a few at a time for the next year rather than digging up the root.|
|Peas||Seeds||Soak your seeds overnight before planting to ensure they sprout quickly. Erect a trellis for them to grow on.|
|Potatoes||Cut up pieces of potato, each with two eyes||Hill up your potatoes by adding soil or dirt extending a few inches up the growing stem once the plant is about eight inches tall. This prevents the new tubers from being exposed to sunlight and turning green. If you’re planting early into cold soil, consider cutting your seed potatoes a few weeks in advance and laying them out in a bright spot so they’ll presprout.|
|Radish||Seeds||Some gardeners plant radish seeds in their carrot rows. The radishes come up quickly and mature before they compete with the slower-growing carrots.|
|Spinach||Seeds||I find that spinach plants usually bolt in the spring, so I generally focus on other varieties of leafy greens.|
|Swiss chard||Seeds||Swiss chard seeds can sometimes be difficult to germinate, but otherwise Swiss chard is perhaps the easiest green to grow and will keep producing all summer.|
|Turnips||Seeds||Like other root crops, turnips prefer loamy, well-drained soil.|
The raw beginner should start out with collards, lettuce, peas, potatoes, radishes, and Swiss chard. Second year gardeners might add broccoli, carrots, and parsley. But ignore my advice if you love beets and hate lettuce — plant what you like to eat!
When to plant spring crops
Every winter is a little different, so I use a soil thermometer to keep an eye on the temperature of the soil and plant accordingly. The thermometer pictured here is actually a meat thermometer, bought for less than $10, but it works just as well as the more expensive soil thermometers you’ll find in gardening stores.
To check the soil temperature, get up early before the sun has hit the ground and insert the thermometer into the ground. Wait a few minutes, then take a reading. If you have garden areas that are more sunny than others, you’ll want to test the soil temperature at several places–I usually find that our soil is two to five degrees colder in the shade of our hillside compared to in the sunnier parts of the garden.
The table below lists the germination temperatures for common spring crops.
|Vegetable||Minimum temp. (degrees F)||Optimum temp. (degrees F)|
In most cases, you can get away with planting once the soil has reached the minimum germination temperature, but don’t plant your seeds if a cold spell is going to set in within a couple of days. You should also be aware that some vegetables will give you spotty germination until the ground was warmed up closer to the optimum temperature — you might want to double your seeding rate to ensure a good stand if planting near the minimum. Once a seed has sprouted, it’s less sensitive to cold soil, so expediting germination by soaking your seeds overnight before planting can also help.
To plant earlier than cold soil will allow, many gardeners are tempted to start seedlings indoors. However, unless you have grow lights or a heated greenhouse, I recommend that beginners stick to growing their plants entirely in the earth for the first year. A quick hoop might be enough to let you plant a couple of weeks earlier than you otherwise could have, then you can transfer the same protection to a new bed in April to jumpstart your summer garden.