People living in the US, Canada, and other wealthy countries are well aware of the health risks of being too comfortable. First, there’s easy access to plenty of convenient processed food, full of sugars and starches and ingredients intended to appeal more to our palate than our physiology. Then there’s increasingly sedentary lifestyles where our hard labor takes place in front of a computer screen, followed by leisure time spent in front of the same screen, or its big brother out in the living room. Strange as it may seem, we could see an increase in overall health if we were suddenly forced to pivot to our stored foods, greenhouses and backyard mini farms. Fresh air, physical labor, nutritious foods free of chemicals and harmful additives… Almost sounds like a holiday retreat we’d pay good money for, doesn’t it?
The goal of providing enough food to keep your family fed through each season while supplying complete nutrition and dietary variety is absolutely achievable. Focus on flexible, easy-to-grow vegetables and fruits that are packed with nutrition. Establish a cycle of warm weather and cold weather crops, depending on your climate, and always plan to store or preserve a portion for later use or in case of a further disaster.
Nutrition
The basic food elements any human needs to thrive include macronutrients such as protein, carbohydrates, and fats; and micronutrients such as vitamins and minerals. A diet composed of relatively light portions of meat, dairy, and/or fish, rounded out with a variety of vegetables, fruits, grains and nuts, will keep our bodies healthy and our energy full. Even better, when we focus on producing food for our own family or small community, we’re able to adapt quickly to changing needs and establish sustainable practices that benefit our bodies, our communities, and the world.
Vegetables and Fruits
- Beans and legumes are highly nutritious. Black beans, kidney beans, pinto beans and soybeans are often celebrated as superfoods. These are excellent sources of calcium and iron, and when dried correctly, they are stable for long term storage.
- Kale and its cousins are particularly rich in vitamins, minerals and fiber. Kale’s cousins include broccoli, Brussels sprouts, cauliflower, cabbage, and collards, all highly nutritious crops that can be enjoyed raw or cooked. Get the most out of your crop by boiling the stems to make a simple vegetable broth, then dumping the remains straight into your compost bin.
- Cantaloupe is tasty and a great source of vitamins A, C, and potassium. It’s fat-free and ranks lower on the glycemic load index than bananas. Even better, cantaloupe ripened on the vine in your greenhouse will have a rich flavor and texture you can’t find from the selection in your grocery store.
- Berries are virtually unmatched for flavor, vitamins and antioxidants. Strawberries and raspberries are well suited to greenhouse growing, but blueberries are more challenging with their preference for acidic soil and plenty of sunlight. You might find that a high tunnel setup is best for blueberry bushes.
The Efficient Greenhouse: Strategic Plantings
Consider Preferences When Starting Indoors
Some plants really thrive with an early start from seed in the greenhouse so they can move quickly into growing once the weather is warmed up. Others do best when they’re planted directly into the ground and left undisturbed. Even when some vegetables might survive transplantation, they may suffer from a prolonged period of transplant shock during which they don’t put on any growth. These plants are better off being sown directly outdoors, even if it means a later start, because they’ll be healthier and more productive in the long term.
Good Candidates: tomatoes, peppers, beets, broccoli, cabbage, collards, lettuce, strawberries and eggplant are all ideal for starting inside. They’ll get a head start on their root development and be ready to start leafing and fruiting as soon as the weather is warm enough for transplant.
Handle with Care: carrots, kale, spinach, and parsley are examples of plants that can do well with transplanting but require extra care and attention. Some options for getting a care-free early start might include providing carrots with a cold frame during the first few weeks for protection from the cold, or growing seeds for spinach and kale directly in pots which can be moved later without disturbing the roots.
Direct Sow only: beans, corn, cucumbers, cantaloupe and other melons, okra, peas, squash and turnips should all be planted where they’re going to live. That could be inside the greenhouse or outside, but the key is to avoid disturbing the plants’ root systems.
Successive Plantings
For fruits and vegetables that you want to keep available all year long, or even just throughout a long season, successive plantings are a terrific strategy. Whether you’re sowing a pot of mixed salad greens, or you want to enjoy fresh young radishes through the season, follow your initial planting with a second, and even a third, a week or two later. As productivity wanes in the original crop, your second planting will be coming into maturity, and so on. As the first planting passes its prime, clear the plots or pots and prepare them for the next crop in your rotation. This practice keeps your crop at peak production while allowing you to make the most of limited greenhouse space. It’s possible to keep a plentiful supply of mixed salad greens all year long with weekly sowings. Change up your mixture from week to week and you’ll never get tired!
Single or Continuous Harvests
Some crops, like corn, carrots, and onions, produce a single crop and are finished. The timing of maturity is consistent, and if you plant a large plot of carrots, you can be pretty sure that they’ll all mature at about the same time. If you want a second batch of carrots or corn, you’ll need to sow seeds again.
Other crops will continue to grow and produce throughout the growing season. Lettuces, cucumbers, climbing beans, and peppers are stimulated to continue growing and producing as long as older leaves and pods are harvested regularly. These long-term producers won’t produce a sudden bumper crop like some single harvest crops can do, but they’ll give you a steady supply with relatively little work.
Tomatoes are the most widely known for their determinate (single harvest) or indeterminate (all season) habits. Interestingly, their production habit is related to the structure of the plant itself. Determinate vegetables usually form bushes of a predictable size and shape, and once the plant has reached a pre-programmed size, it will begin to bloom at set fruit, all at once at the end of each individual branch. The fruit grows to maximum size and then ripens within a few days. This type of tomato (Romas, for example) is ideal for canning since you have a large crop that ripens all at once.
Indeterminate tomatoes grow somewhat randomly and should be trimmed back so they spend their energy on fruiting rather than taking over the garden. Their flowers emerge throughout the season at nodes along the stem and branches and continue to produce until the weather is too cold. These are ideal tomatoes for salads, for fresh pasta dishes and tasty summer sandwiches.
Warm Season and Cold Season Vegetables
Certain crops are programmed to bloom and set fruit during long, warm sunny days. Summer squash, tomatoes, sunflowers, eggplants, melons, Mediterranean herbs and hot peppers all prefer warm temperatures and will produce prolifically in season. If your greenhouse stays warm in wintertime, you can continue to grow most of these year-round, so long as your greenhouse continues to get adequate sun.
If your climate is too cold to keep your greenhouse warm during the depths of winter, never fear. Cold season vegetables and fruits (strawberries, anyone?) will be happy to grow, so long as the minimum temperatures don’t dip below that species’ preferences. (Seed packets are your friends!). In fact, many winter vegetables such as Leeks, Brussels sprouts, kale, cabbage, and more, don’t reach their peak flavor until they’ve been subjected to frost. Many root vegetables such as beets, carrots, turnips and parsnips are at their sweetest after the first frost but before the ground freezes.
Whether you’re operating a heated or unheated greenhouse, you’ll get your widest variety of fruits and vegetables through the year by following the natural seasons for your crops. Take advantage of this kind of opportunity to bring changing flavors and a full spectrum of nutrients to your table.
Organize Your Greenhouse
If you’ve got some favorite warm season vegetables that you want to continue with through the winter (tomatoes are a popular choice!) while still taking advantage of the cool season bounty, it may be easier than you expect, depending on the structure of your greenhouse. If you’ve got a relatively small selection of plants that need extra cozy temperatures, consider sectioning one end off from the main greenhouse by erecting a temporary wall. You can supplement the available heat with a small composting unit which will have a much higher impact in a more confined space.
Use the greenhouse and cold frames strategically during spring and autumn - the cold frames can extend essentially the same protection as your greenhouse, and if you build frames that are lightweight and sturdy enough to sit directly on top the ground, then picked up and moved to a new area, you’ll have a highly adaptable system to support the maximum food production.
Plan which crops will be rotated indoors and outdoors as the seasons progress, and plan where they will go so there’s no overlap but also no long periods where nothing’s happening in any section. Greenhouse space is valuable - don’t let it go to waste!