Cold Frame Gardening: Extend Your Growing Season

A cold frame is like a mini-greenhouse. It is made of wooden sides, a glass cover that can be vented, and holds rich soil. The cold frame can be used in early spring to start seedlings, to harden-off plants started indoors, or to protect vegetables in the winter. A cold frame will keep vegetables 10°–20° warmer than the ambient temperature.

Savoring the rich taste of vegetables just picked can be addictive. Many families have recently begun vegetable or victory gardens to save money and to have local produce available throughout the warm weather months. The pleasure of growing your own and enjoying the health benefits of unprocessed foods makes a gardener wish that summer would never end.

But, of course, it does end and cold weather comes eventually. However, cold weather does not have to mean the end of growing vegetables. A simple cold frame allows gardeners to have fresh vegetables into the winter and for those in hardiness zones 7–9, a cold frame may be viable throughout the entire winter.

Just imagine, going out to your yard in December and harvesting greens for a dinner salad.The fresh picked lettuce and spinach will taste so much better than the store-bought products shipped from Mexico or California. The cost of fresh produce will be less also. You will be measuring it in terms of pennies and not dollars.

How Does a Cold Frame Work?

A cold frame traps the sun’s heat through the glass cover and holds the heat in place with its wood or cinder-block frame. Plants are protected from the elements and the soil retains heat to keep the plants thriving. A well-positioned cold frame will have a sloped roof with a southern exposure. The roof will be made of framed glass.

Cold frame covers or roofs can be made of old, framed windows or storm doors. If you do not have framed glass, acrylic can be placed in a frame and used.

The size of a cold frame is dictated by the dimensions of the cover. If wood is used for the sides of the frame, choose a wood that tolerates dampness such as cedar or redwood. Most people paint their cold frames to add protection to the wood surface.

Once the frame is built and the cover installed, add well-composted soil deep enough to provide growing room for roots—usually 12”–18”. Cold frames are built on an angle with the back of the frame being 50% higher than the front thus providing a slope for the glass cover.

It is essential that your cold frame have the ability to be ventilated because even on winter days when the ambient temperature is above freezing, it can become too hot.

Wood pieces or concrete blocks can be used to prop the cover and allow hot air to escape. Or, if the cover has sliding panels, just open them during the heat of the day. Don’t forget to close the cover at night or when the temperatures are below freezing. If the temperatures are very cold—low 20’s or teens—use a blanket or burlap cover at night.

What Crops can be Grown in a Cold Frame?

  • Leaf Lettuce
  • Spinach
  • Radishes
  • Carrots
  • Onions
  • Chard
  • Mesclun
  • Parsley

A cold frame for winter vegetable gardening or protecting new plants is an excellent investment as well as a source for fresh, healthy produce. A cold frame is relatively easy to build or a kit can be purchased relatively inexpensively.

Once your building project is completed and the cold frame has been filled with rich, composted soil, you will be able to grow and harvest a wide variety of salad greens in the fall, winter, and early spring.

The Benefits and Drawbacks of No Dig Gardening: Reasons For and Against Digging on Different Types of Garden Soil

Many people enjoy digging. If done properly and methodically digging is an excellent form of exercise in the fresh air. The sight of well-turned, crumbly soil replacing weedy, compacted land, and watching a robin seek out grubs as it follows the spade more than compensates for any resulting aches and pains. But, for those gardeners who don’t like digging, or are unable to do so due to age or disability, the notion of no dig gardening can be very appealing.

The Case for Conventional Digging

  • The spade or fork can relieve compaction instantly.
  • When the soil is turned over by digging annual weeds are buried, which will rot down.
  • Where heavy clay soil is dug and left in large clods over winter water penetrates and freezes breaking up the soil to produce a finer tilth in spring.
  • Soil-inhabiting pests are brought to the surface when you dig, to be eaten by birds or killed by frost.
  • Deeply dug soil is essential when planting trees, shrubs and perennials to ensure a large root system for anchorage and the easy extraction of water and nutrients.

The Case Against Conventional Digging

  • Without digging weed seeds remain buried, many failing to germinate.
  • Beneficial organisms remain in the soil safe from predators.
  • Where light sandy soil are dug in the autumn heavy winter rains pounding on the surface damage the soil structure.
  • Winter rains easily pass through cultivated soil carrying nitrogen and other plant nutrients with them.

The Case for No Dig Gardening

  • Less physical effort is required, because after initial cultivation the soil is never turned over.
  • Mulch and fertilizer are spread over the surface each year and this is pulled down into the soil by earthworms and other organisms.
  • Drainage and aeration are improved through the channels left in the soil by the worms, whose casts deposited on the surface create the ideal seed bed.

The Case Against No Dig Gardening

  • Heavy clay soil compacts easily and is much harder to cultivate if not dug.
  • Large puddles form on heavy soils which aren’t dug.
  • No dig gardening relies on large quantities of compost or other mulch being available for spreading over the soil to control weeds.

So the No Dig Method is Not as Easy as it Sounds, but Does Have its Attractions

Even with the no dig method there is some initial pain. Digging to a spade’s depth and breaking up any hard pans is essential when embarking on this way of gardening. Although annual weeds can be hoed off, perennial weeds with extensive root systems must be dug out.

If you have a soil which isn’t too heavy and you grow vegetables using the bed system the soil is not compacted around the plants. Work is done from permanent pathways with 1.2 meter wide beds reachable from either side.

So if annual digging isn’t your idea of fun, then do it once, do it well, set up a bed system and let nature dig for you.

Lunar Gardening: The Principles of Planting By The Moon

The Chinese, Greeks and Romans were all guided by the moon and their principles for using its phases was based on practical knowledge. The moon not only controls the tides but also defines the moisture content of the earth. When taking account of the correct phase of the moon and the most beneficial Zodiac sign, garden activities and results can be very positive.

Luna Gardening and the Moon Phases

All water is affected by both the sun and the moon. The magnetic pull of the smaller moon is much greater because it is much closer to the earth. The moon affects the on earth in different ways depending on whether it’s an increasing or decreasing moon.

A waxing moon is a growing moon and the time when moisture content in the earth is at its highest. Crops and seeds planted during this time are able to access the water more easily. A waning moon is when the moon is decreasing and the moisture content is at its lowest. It is best to undertake other activities such as pruning and weeding during this time. The moon also has four quarter phases.

  • First Quarter Increasing – from the New moon up to the first quarter – the moon is getting bigger
  • Second Quarter Increasing – from the first quarter moon until the full moon
  • Third Quarter Decreasing – from full moon until third quarter moon – the moon is getting smaller
  • Fourth Quarter Decreasing – from the third quarter until the full moon

Lunar Gardening and the Zodiac Signs

Each Zodiac sign has its own significance within lunar gardening. One sign dominates each day and every sign is present at least once a month. Each Zodiac sign is ruled by a particular planet which again influence water levels, tides and the wind. The signs are divided into three distinct categories and have a different part to play in the gardening calendar.

The Cardinal Signs

So called as they are situated at the east, west, south and north of the astrology chart and correlate to the points of a compass.

  • Aries tends to be dry and barren so good for cultivating, weed and pest management, and harvesting
  • Cancer is moist and considered one of the more productive signs for planting, seeding and irrigation
  • Libra is airy but moist, used for planting where good roots are desirable – especially vines and flowers.
  • Capricorn is earthy and good for planting potatoes, fruit trees and bulbs

The Fixed Signs

They represent a balance of conflicting forces and are known as the foundation signs. They have great reservoirs of energy.

  • Taurus is moist and earthy – good for many root and leafy crops
  • Leo is the driest sign of all and not useful for planting. Weed and pest management and harvesting is best during this time.
  • Scorpio is moist and watery, sturdy time. Most vegetables and plants can be planted during this time
  • Aquarius is another dry sign in terms of lunar gardening, best for harvesting and pest management.

The Mutable Signs

These quick signs act as mediators between the other two categories.

  • Gemini is dry and not a good time for planting or transplanting.
  • Virgo is a moist but barren sign and another good time for weed and pest management. For flowers and vines it is good for planting.
  • Sagittarius is barren and dry but good for onion, garlic, peppers and chili. It is also an ideal time for cultivation and harvesting.
  • Pisces is watery, one of the more fertile signs so good for planting most kinds of crop.

Understanding the forces of the moon and its corresponding Zodiac sign for managing the produce from the garden can be beneficial. Trial and experimentation which takes into account local seasonal changes will help the gardening calendar go to plan.

Gardening in the Snow: Even in Northern Climates, Fresh Produce Can Be Harvested in Winter

Imagine adding fresh, homegrown vegetables to the menu at Thanksgiving, Christmas, or Easter. By planting crops that withstand frigid temperatures—and by utilizing practices that will make one’s local climate a USDA zone warmer—fresh-from-the-garden produce can still be brought to the table long after most people have tilled their gardens under for the winter.

Even in areas with severe winters and deep snows, growers can enjoy a measure of self-sufficiency (not to mention tastier vegetables) by extending their harvesting season far into winter.

While it may be difficult to produce an abundance of food twelve months of the year in every locale, most gardeners can eat fresh cauliflower or broccoli in late autumn and early winter, Brussels sprouts from October through December, and carrots and greens throughout the winter.

Furthermore, with forethought and planning, some vegetables can be overwintered in the garden and harvested as early as February in many northern areas.

However, if one is to harvest vegetables in the fall and winter, they must be sown in the summer and fall. Traditional crop rotation, tilling, mulching, and fertilizing practices will probably need to be altered to accommodate the increased utilization of the same space.

Winter Gardening Basics

  • When planting a crop for winter production, do not plant it in the same bed as summer’s crop.
  • Reduce tilling to a minimum. Studies show that symphylans remain active in cold soils, where they normally feed on fungal strands. Tilling disrupts fungal strands, forcing symphylans to feed on plant roots.
  • Cold temperatures reduce the activity of soil microbes, rendering winter applications of fertilizers and other amendments less effective. Organic fertilizers, compost, bone meal, etc., should be worked into the soil when temperatures are warmer.
  • Use row covers (e.g., Reemay, Grow Guard) to protect crops that are transplanted to the garden in late summer. Insect pests will remain active until a killing frost reduces their numbers.

Crops That Lend Themselves to Winter Gardening

Cole crops are generally more cold-tolerant than other crops. When subjected to cold temperatures, they concentrate sugars in their tissues; these sugars act like anti-freeze that prevents leaves from freezing and imparts a sweeter flavor to the produce.

  • Broccoli: To enjoy continuous production, start different varieties of broccoli indoors in mid-June. Transplant to the garden in early August; harvest heading types in late fall and early winter, and sprouting types into late winter and early spring. (‘Apollo’, ‘Thompson’, and ‘Veronica’ mature in late fall; ‘Rudolph’ and ‘Purple Sprouting’ are late-maturing, sprouting varieties)
  • Brussels sprouts: Most cultivars are extremely cold hardy (down to 10º F). Start indoors in early- to mid-June, transplant in early August, harvest into late winter and early spring.
  • Greens (Collards and Kale): Start indoors June through July, transplant August into September, harvest as needed all winter (greens don’t last long once picked). Kale is an excellent stir-fry green, while collards are a traditional potherb.
  • Cabbage: Plant fall/winter varieties June – July, spring varieties in August (start indoors in hotter climates). Harvest fall varieties September – October, winter varieties in December, and spring varieties March – April. (Varieties: ‘Melissa’ for fall; ‘Deadon’ for winter; ‘Tundra’ or ‘January King’ for spring)
  • Cauliflower: Early varieties can be started indoors in June, transplanted in August, and harvested when mature in autumn; late varieties are started in July, transplanted in September, overwintered, and harvested the following spring. (Varieties: ‘Amazing’ and ‘Cheddar’ are early; ‘Lundy’, ‘Galleon’, and ‘Maystar’ are late)

Several root crops grow well in cooler temperatures. Once mature, they can remain in the soil through the winter down to zone 5 (a foot of overlying straw will make them easier to dig and even get them through the winter in zone 4). For colder areas, these crops can be dug when mature and stored in dry straw or damp sand.

  • Beets: Plant late crops in July or early August. Cooler fall temperatures promote even growth.
  • Carrots: Plant late crops in September, keep moist until sprouting occurs. Good varieties for fall crops are ‘Bolero’, ‘Yaya’, or ‘Dragon’. Overwintering cultivars include ‘Autumn King’, ‘Imperator’, or ‘Merida’.
  • Parsnips: Plant out in June – July, harvest all winter.
  • Turnips: Plant out from mid-July through August, harvest all winter.

Many other crops, including lettuce, spinach, chard, mustard, and endive, can be nurtured beneath low-cost cloches and cold frames for continuous winter production in many areas. These structures, which effectively increase the USDA growing zone, can be reinforced in areas of heavier snowfalls to protect nearly any crop…and maintain access for the hardworking gardener who deserves that mid-winter reward of fresh produce.