For not having brains, plants are a very smart organism. One thing that they can sense that we cannot is day length.
Tomorrow we will experience exactly eleven hours of sunlight. For plants this is a magical number, when the sunlight is below 11 hours plants remain dormant. After 11 hours vegetable plants will start to grow again. For me this is when I will start growing transplants in the greenhouse; for gardeners with cold frames, their plants will begin to perk up.
There are many plants that have special day length requirements. Onions are one of these crops. Their bulb production begins while day length is shortening past a peak. The two types that are grown here in the Northeast are long-day and intermediate day. Long-day onions begin to bulb up after 14 hours of sunlight have been achieved, intermediate day begin to bulb up after 12 hours have been achieved.
I look forward to the increasing sunlight hours and the growth it will bring!
Last week we learned about cold frames. We learned how they work, what they are made of, and what their purpose is. This week we will learn about crops that can be grown in them.
Most of the crops Americans like are chill sensitive crops, they do not thrive below 50 degrees: think peppers, tomatoes, and corn. To find crops that will grow in the cold, a seasoned gardener will look to Europe for variety.
European gardeners have been making gardening work in the winter for a long time. Some popular crops that come from this experience are: Mache, Escarole, Endive and Radicchio.
Mache, known as corn salad, is a sweet, nutty juicy green. In 17th century France it was first seen as a weed, growing in fields, of corn, rye and wheat. Its cold hardiness was identified and it became domesticated in home gardens.
Escarole and Endive are in the same family of crop and their names are often interchanged. Endive has a lacy leaf, and is a bitter green. Escarole has a broad leaf, and is less bitter.
Radicchio looks similar to a red cabbage. It has red leaves and white stems, is bitter and spicy. It is a vegetable that is best grilled or roasted.
In addition to these exotic vegetables, many of our common vegetables work well in a cold frame. Salad, Spinach, Carrots, Leeks, Beets, Radishes, Turnips, Kale, and Chard all grow well in a cold frame.
A cold frame is a raised bed with a translucent lid; either glass or plastic used to retain solar radiation. Cold frames are used to grow produce when the weather is frigid.
Solar radiation warms the soil in the cold frame during the day, this heat is released but captured by the lid creating a warm micro-climate. This micro-climate allows crops to grow during the harshest times of the year.
A cold frame is best utilized going into spring and going into winter. Hardy greens can be started in late winter during warm spells, much like the one we just had. With a little moisture and a few warm days, germination happens. The warm environment allows the plants to grow, or at least stay alive through cold weather and temperature fluctuations. They will continue to grow and be ready for harvesting before a gardener can plant in their outdoor garden.
The second time to use a cold frame is going into the winter. Seeds are planted in late fall and the crops quickly grow to maturity. Crops will not grow during the harshest weather, they will sit waiting for the next warm day. With a cold frame this can be used to a gardener's advantage. In January when the weather is coldest, these mature crops sit in dormancy. As they are fully grown, gardeners can harvest them through the coldest month.
A cold frame can be made out of an old glass door, or using polycarbonate, a twin-walled plastic used to build greenhouses. Glass door or windows can be used by thrifty gardeners to make a successful cold frame. Gardeners must be wary of burning their crops when warm weather returns however. I build my cold frames out of polycarbonate because it is light, then put an automated lift arm on the lid. This lift, which is a wax cylinder, expands as the weather warms and when it becomes too hot, it opens the lid and vents some of the heat. This fail-safe is especially useful for gardeners who spend their day at work. With temperatures that can spike long after the gardener leaves the house, this fail-safe is a no-brainer.
Tune in next week for good crops to grow in a cold frame.
In a few weeks Lowe's and Home Depot will start selling trees and shrubs in their garden section. Buying a fruit tree at a big box store is like buying a Christmas tree at a box store; they'll have them, but their quality is going to be terrible.
According to the the University of Illinois Extension Service there are over 2,500 varieties of Apple trees grow in the United States of America. Not all of these varieties are suggested to be grown by a home gardener. As we learned in last week's insight, fruit is one of the most chemical laden food groups on the market, and there are reasons for that. With mass production of any food source pests and diseases will exploit it. To keep the fruit production safe from pests, fungicides are sprayed on a schedule to keep diseases at bay, and insecticides are sprayed to rid orchards of insects.
Home producers of fruit do not have access to these chemicals, nor would we want to, they are downright bad, bad for the planet, bad for the applicator and bad to eat as a residue.
While some fruit trees were bred for their visual appeal (the modern human tastes with their eyes rather than their mouth) or shelf life (those apples we eat in spring have to come from somewhere that is experiencing the beginning of fall), others were bred for cold hardiness, or resistance to fire-blight or scab. The Pennsylvania State Extension Service offers their list of disease resistant varieties to be grown in Pennsylvania. I use these lists to decide which fruit trees Wilson Home Farms will plant. These lists can be found here.
In addition to good varieties there are nurseries that are better than others. Some nurseries will sell you any fruit tree at any time of the year. That is a hint that they are not a good nursery. There is a specific time to plant trees and there are certain trees that should not be planted in Pennsylvania. Nurseries like Adam's County Nursery grow fruit trees in Pennsylvania and only will ship out their trees once a year, in late winter, after the ground thaws and before the buds burst.
So before you buy that pretty flowering peach tree from the box store, remember, there is a lot more to the investment than the tree.
Wilson Home Farms plants fruit trees in April. Order now, before March to get them in this year! Popular varieties for home gardeners are selling out quickly.