While it's true that you can get started growing right out of the box with your new greenhouse, 99% of greenhouse growers use some simple tools to help monitor and maintain ideal growing conditions in their greenhouses. Whether it is keeping things cool during hot summer months or making sure that overnight lows don\'t drop below 45 degrees in the chill of winter, there are a variety of greenhouse accessories that will help maximize your greenhouse productivity. In this article, we discuss some of the most essential and popular accessories that we recommend to our customers. 
Thermometers: One of the most important aspects of greenhouse growing is temperature control. Maintaining the proper temperature is vital to ensuring optimal plant health and growth. So it stands to reason that one of the most important accessories for your greenhouse is a thermometer. We recommend a Min/Max thermometer so that you can track how hot your greenhouse gets during the day and how cold it gets at night. You'll want to keep a log of these temperatures as well as the outside weather conditions in order to get a sense for how your greenhouse performs under different weather conditions.
The latest innovation we've seen in monitoring greenhouse temperatures is the Weather Station which lets you monitor conditions inside and outside your greenhouse from the comfort of your home! This gives you all of the data you need to monitor how your greenhouse performs year round, allowing you to plan for and anticipate what you'll need to optimize greenhouse growing conditions.
Vent Openers: The most popular accessories people choose for their greenhouses are automatic vent openers . These inexpensive devices help keep greenhouses cool by automatically opening as the greenhouse warms during the day. Once the vents are open, ventilation also is improved as the hot air rises up out of the vents, drawing cooler air in from the bottom of the greenhouse and maintaining a good air circulation.
Circulation fans: Keeping the air moving in your greenhouse is vital for the health of your plants. If the air around your plants isn’t moving, your plants are more susceptible to disease from fungus. Additionally, if the air around your plants is still, they can deplete the amount of CO2 in their immediate vicinity, slowing their growth. When airflow in your greenhouse from ventilation is minimal, or if you have a larger greenhouse, you will want to use Horizontal Air Flow (HAF) fans to make sure that your plants are getting fresh air circulating around them.
Shade Cloth: Another key element for regulating the temperature of any greenhouse is a shade cloth . Even in moderate temperatures, a greenhouse that gets full sun can still reach high temperatures that can damage your plants. Shade cloths will not only block some of this heat but they will also help to diffuse the light entering your greenhouse. Typically, shade cloths are made from a mesh weave of plastic. However, a popular recent innovation, called Aluminet , incorporates metal to increase the reflectivity of the shade cloth, thereby reducing solar heating even more.
Misting and Watering: Another option to help keep your greenhouse cool is to use a misting system . This can be run either on a timer or on a thermostatically controlled outlet.
Heaters: During the winter it is important that you try to maintain overnight temperatures above at least 45 degrees Fahrenheit. Some tropical plants may require even higher temperatures. There are a variety of ways to help maintain high overnight temperatures in your greenhouse, however most growers in colder climates will find the need to use a heater at some point during the winter.
To calculate the heating requirements for your greenhouse, it will be necessary to factor in the size of the house, the insulation factor of the glazing and the difference in temperature that is needed. We’ve made it easy for you by providing this calculator:
There are three major types of heaters. Electric heaters such as Juliana Flexifurnace Heater provide safe reliable heat for smaller houses or when a greenhouse in normally moderate climate experiences a prolonged cold snap. One tip is to use two electric heaters with one set slightly lower than the other so that it only turns on when extra heating is required.
If you need more heat, it may be necessary to install a propane or natural gas heater. These heaters are also normally safe for you and your plants. Look for heaters that will automatically shut off when their Oxygen Deprivation Sensors (ODS) detect.
Finally, although all of the heaters we sell are very safe and reliable, a prudent greenhouse grower will have a general purpose fire extinguisher available. These will be denoted with the term ABC. Also, remember to periodically check them - Better safe than sorry!
Ground Cover: Ground cover is an essential to lay underneath your greenhouse. This specially designed plastic fabric permits water to drain out of your greenhouse while preventing weeds or pests from coming in.
Shelving: Whether you build your own or buy it, you get much more satisfaction out of your greenhouse by making sure you have some convenient shelves. They not only give you more space for keeping plants, but they can provide essential work areas while you are working with your plants. The ideal potting shelf will be at a height where you don’t have to bend over far to work with your pots and plants. The ideal growing shelf will have ventilated shelves to allow for water to drain and light to filter through.