Feeling the Winter Gardening Blues? Try Starting a Greenhouse!
For the passionate gardener, a greenhouse is a great way to lengthen the growing season. You can get a head start on seedlings for your garden and protect tender plants during the winter. A greenhouse is a good option if you want to start and maintain a collection of plants like orchids or other tropical flowers.
Making your greenhouse environment successful takes planning. A good design and proper placement of the greenhouse is essential. It goes without saying that you will want to site your greenhouse in a sunny location. It is also important to consider terrain, wind direction, access to water, power, and drainage. Greenhouses come in a variety of materials, sizes, and price ranges, and can be pre-fab or custom-built. Careful planning for your growing needs – whether starting seedlings for your vegetable garden, protecting tender ornamentals, or maintaining your collection of tropical plants – will help you make the best choices for your greenhouse structure.
Whatever greenhouse structure you choose, there are certain fundamental best practices for growing and maintaining healthy plants. Here are some tips to keep in mind.
A Clean Environment
The closed environment of the greenhouse can be a magnet for a variety of plant diseases and pests. These can be soil-borne, water-borne, or air-borne. Being vigilant about cleanliness in the greenhouse will go a long way in keeping your plants healthy. When working in the greenhouse, plan time at the end of your day to clean up. Remove empty, soiled plant pots. Discard any standing water. Pick up and discard all plant debris. Sweep floors, and mop them once a week.
Every green plant needs light for photosynthesis to make food. When you build your greenhouse, most likely you’ll look for the best location with best sun exposure. If your greenhouse is located in an area with a rainy climate, you’ll probably want to supplement with artificial light sources. Getting to know the light requirements of your plants is important. Too little light may cause your plants to stretch or become “leggy,” developing thin, weak stems. Too much light can burn tender plants and seedlings. As light can cause heat to accumulate, you might find plants drying out too quickly. Keep plants spaced apart properly so that they receive adequate light. Supplement with artificial light as needed. Use shade cloth to protect plants when sunlight is too intense.
Plants kept in the greenhouse are almost always planted in a soilless medium – a medium which does not contain soil or topsoil from outdoors. Soilless mediums are comprised of components such as peat moss, sphagnum moss, perlite, sand, compost, and other soil amendments. Making a soilless mix presents the possibility of tailoring soils for specific plants. Ferns and orchids need very different soil mixes from a cactus, for instance. Also, choosing the best and cleanest soil components will help greatly in reducing soil-borne problems in your greenhouse.
Every plant needs water. Some plants grow in water, like the water lily and various rushes. Some need water only on an occasional basis and in very small amounts, like cacti and other succulents. Getting to know the moisture needs of your plants is crucial to their health. Careful daily observation of your plants is important. Look for wilting leaves and dry-looking soil as well as water-logged plants in poorly draining soil. Most importantly, pick up the pot – a dry pot will feel very different from a well-watered pot. When you water your plants, be deliberate so that you do not miss a plant. Water carefully at the base of the plant and avoid getting water on the leaves.
Plants come to us from so many different climates from throughout the world. When we grow plants in a greenhouse, we need to be sensitive to growing requirements of natural habitats – proper temperature is very important among these. Many plants succumb quickly to broad temperature fluctuations, whether too hot or too cold. Other plants need temperature fluctuations to set flowers, while some plants need a period of complete dormancy. Get to know the temperature needs of your plants. Keep a thermometer in your greenhouse and record high and low temperatures. These records will help you make needed changes in temperature. Temperature changes can be made by fans, roof and side vents, pad cooling systems, heaters, or by simply opening a door. Having heating and cooling devices linked to a thermostat control will help you regulate temperature efficiently.
Proper airflow and good ventilation are very important to the health of plants in your greenhouse. Good ventilation and airflow help with temperature and humidity control, mitigate pathogen and insect populations, regulate levels of oxygen and CO₂, and may help with pollination. Even on the coldest winter day, sunlight can be intense, creating high temperatures inside the greenhouse. Opening ridge and side vents, even for a short period of time, will help regulate high temperatures from accumulated heat. In smaller, less complex greenhouses, just opening doors will help.
Even when your greenhouse temperature is stable, air movement is important. It can affect many plant functions which keep plants healthy. Some greenhouses have intake vans regulated by a thermostat. A less-expensive alternative is an oscillating floor fan placed correctly in your greenhouse; it will help distribute airflow evenly.
A greenhouse is a great way to grow plants and enjoy them throughout the year. Give your plant collection a good start by selecting healthy plants and placing them in proper growing medium. Check on your plants daily; conditions within a greenhouse may change quickly – day to day, or even hour to hour. Keep track of temperature and humidity. This will help you make needed adjustments to light, watering, and air flow. Most of all, don’t forget to keep your greenhouse clean and tidy and free from debris. Both you and your plants will enjoy this healthy environment!