Greenhouses are available in all sizes, shapes and degrees of strength. They can be bought in unassembled packages, assembled on site and ready to set on foundations, or custom designed for a specific need. Most greenhouse structures fall into three types. The attached lean-to greenhouse has one sidewall as a part of a house, garage or other building. The lean-to is less expensive to operate and construct, but there may be some drawbacks in cooling or ventilating this type of greenhouse.

The window design greenhouse is attached outside a conveniently located window and may be an economical solution for some homeowners. It's very challenging, however, to maintain a uniform temperature in this type of greenhouse because heat is dependent on the interior home heating.

The free-standing greenhouse is the most versatile, when maintaining a good greenhouse environment. This type of greenhouse is easy to ventilate all year long, and can be easily expanded if necessary.

When considering where to place the greenhouse, consider the exposure the greenhouse would receive from a certain location. An eastern or southern exposure is the best for the lean-to greenhouse. Locate the greenhouse out of shade, especially in the winter months.

Materials for the framing of the greenhouse may be composed of untreated wood, aluminum alloy, steel stone or brick. The material you may decide upon will depend on the budget, durability, types of plants to be grown and aesthetics of the structure. If a wood framework is chosen, use a type without wood preservatives, such as Penta or creosote. The most popular woods, western red cedar or Douglas fir, resist rotting and are a good choice for greenhouses. Aluminum and steel are generally colder than wood but in small greenhouses the amount of heat loss due to this factor is limited. Aluminum generally requires less maintenance than a wood structure.

 

Houseplants: Temperature & Humidity

Light, temperature and humidity are the most important factors for houseplant health. Many plants typically grown as houseplants are native to the tropics where environmental conditions are much different from those of a Colorado home. To improve their chances for survival as a houseplant, it may be necessary to provide supplemental humidity or light or to place the plant in a cooler or warmer area of the home.

Although houseplants tolerate temperatures that are slightly lower or higher than ideal, less than optimal environmental factors affect growth and quality. The temperature preferences of indoor plants are categorized as cool, intermediate or warm. Cool is 40 to 50° Fahrenheit, intermediate is 60 to 75° F, and warm is greater than 75° F.

Humidity, the level of moisture in the air, affects a plant's need for water and its health. Plants routinely move water and nutrients from their roots to the stems and leaves using a process called transpiration. When the water reaches the leaves it is released into the atmosphere through tiny openings. High humidity slows this water loss. Plants grown indoors with low humidity or in a draft lose more water through transpiration, so their root systems require more water.

During colder months, heating systems circulate dry, warm air throughout the house and in summer, air conditioning systems circulate dry, cool air. Both of these conditions often create an environment that has less than 10 percent humidity, well below the 70 to 90 percent relative humidity levels found in the native climates of most tropical plants. In addition, plants located near heating or cooling vents are subject to increased air movement that increases transpiration. Many develop leaf spots or brown tips as a result of the lack of humidity.

Misting plants may help alleviate this condition. However, it must be done frequently to be effective, and it may promote some foliar diseases. A better solution is to group several plants together on a tray filled with gravel and water. The evaporating water provides the humidity the plants need. The bottoms of the containers should stand above the water so the soil will not become water-logged and cause root damage. Using humidification devices around the tropical plants will also help.

In contrast, many cacti and succulents native to arid, desert conditions adapt well to the low humidity conditions in our homes and are great candidates for houseplants.