Archive for January, 2006

Ventilation

Your plants should reach the market in tip-top shape, which will not happen if your greenhouse is too cold, too warm, or too drafty. So you should pay close attention to ventilation. Automatically controlled (thermostat) ventilators are helpful and relieve you of constant attention. If you don’t have them, open the ventilators first thing in the morning if the day is due to be hot-regardless of the calendar. During the summer, I leave the ventilators open all the time. In spring and fall, take care that cold drafts do not blow directly over plants. The best way to ration fresh air is to open the ventilators a crack at a time, thus avoiding sharp declines in the inside temperature.

Ridge or side ventilators, and exhaust fans are available for greenhouses. If you are using side vents, be sure that they are arranged in a way that will not cause the air to blow directly across your plants. Louvered side vents provide excellent service and can function as part of the summer cooling system you may eventually wish to install. Plants such as cymbidium and cyclamen require rather low temperatures part of the year- another good reason for a cooling system.

The large commercial grower in a huge greenhouse-with his constant personal attention, abundant water supply, and great body of air overhead-can well afford to have an opening in the roof as a means of ventilation. But not so the person with a typically small, low-roofed, hobby greenhouse. Too much air can escape in a short time. And it is not only the hot air that escapes through a roof vent; with it goes the humidity the plants need so very much.

Automatic ventilation, via a fan system, changes the air completely every 3 minutes. With the fan in operation only briefly, your plants benefit from whatever humidity is in the greenhouse. You can purchase manual ventilator openers made of metal, or by investing a little more, you can install automatic openers. These are hooked up to thermostats and will open and shut ventilators whenever a change of air is advisable.

Organic Mulches

Mulches minimize evaporation and reduce the amount of weed growth. By using mulch, it will make you xeriscaping a success. Organic mulches such as wood chips or bark are the best choice. Never use any solid plastic under the mulch or anywhere else in the landscape.

Good pruning, weeding and fertilization will preserve and enhance the quality of the xeriscaping that you do. All the prospects of xeriscaping will ensure a healthy and attractive landscape with the use of the proper amount of water.

Plan and think out your design

Make sure that you have a plan. Find out where things are and consider the view, the slope and the sun exposure. Take into consideration the existing vegetation and the site that you are intending to design.

Improve the conditions if necessary

Soils will vary at every given site. If you have poor soil, you will want to give it the nutrients that it needs to get in shape for your xerscaping process. Adding compost to your soil will bet it into top shape for your plans.

Picking your plants

Most plants are fine to use with xeriscaping. Selecting the plants should be based on the intended use in you landscape design. Use plants with lower watering needs and this will allow the maximum water conservation for you.

Irrigation systems

You should plan out your irrigation system well. Irrigate turf areas separately. Group the plants that have the same needs together. Not all plants have the same watering needs. Irrigation needs will change with the season and the weather. You will need to irrigate according to the condition of the plants instead of on a maintenance schedule.

Emergency Heating

Even the best heating facilities sometimes go wrong, and an alarm system has little value unless you have on hand some emergency heating equipment, ready for use. My emergency setup consists of two portable electric heaters. I set them on boxes, one at each end of the greenhouse, and place an electric fan behind each of them. Although not recommended for daily use, this setup serves the purpose and keeps plants from freezing or chilling and so suffering a setback in growth.

A still simpler from of emergency heating can be provided with a candle inside a flower pot. Light the candle, then invert a similar sized pot over the first one-pot rims together. The candle will receive oxygen through the hole in the top pot. Place several of these heaters around the greenhouse and you will maintain an above-freezing temperature. The number of these units you’ll need will depend on the snugness as well as the size of your greenhouse.

Operation costs

In many sections of the country heat is the most expensive item in greenhouse operation; in other areas it is negligible. Any manufacturer who specializes in greenhouse building will give you accurate estimates of heating costs for your location and greenhouse during an average season.

Or a local plumber may advise you. A friend in Michigan who uses a forced-air circulating heater for her seven-section redwood house finds the cost about $35.00 per season to maintain 50-degree temperatures at night and 60 during the day. A Minnesota grower, employing hot water for the same sized house, keeps it at 65 at night, 75 in the day, at an estimated cost of $105.00 per season.