how to grow organic vegetables in a greenhouse


Many growers tend to ask the difference between vegetables, herbs, and fruits.  A vegetable is a plant or any part of a plant that is considered edible and can be eaten.  Herbs, on the other hand, refer to plants or part of plants that are grown as food and also for medicinal purpose while fruits are eatable products containing seeds which are formed from the matured ovary of a flowering plant.  The major difference is that while fruits can be referred to as vegetables, vegetables cannot exactly be termed fruits. Also, it is arguable that not all herbs are eaten as the main ingredient as is the case of vegetables.

Growing Vegetables in a Greenhouse

Vegetables are suitable plants to cultivate in a greenhouse because the demand for them is usually high all through the year.  However, the vegetables require the right environmental condition for successful cultivation.  The grow lights in the greenhouse should be energy efficient and cover the vegetable plantation.  During the cold season, the best vegetables to cultivate include; tomatoes, lettuce, spinach, peppers, and cucumbers.  But with experience, any kind of vegetable can be successfully cultivated when provided with the right temperature.  The key is to maintain a nighttime temperature between 40 – 62ºF in the greenhouse depending on the type of vegetable.  One of the major issues growers face when it comes to growing vegetables in a greenhouse is the issue of pollination.  While some vegetables like tomatoes and peppers can self-pollinate, the others that cannot self-pollinate will require hand pollination.  This is achieved by taking the anther of a vegetable and rubbing it carefully against the stigma of another vegetable for a successful transfer of pollen grains.  Sometimes, the vegetables that can self-pollinate require being shaken in order to successfully pollinate but a circulation fan can be installed for this purpose.

Vegetables need water but not too much and so it is important not to overwater your greenhouse vegetable garden.  A good ventilation system in place will maintain the proper humidity level which will aid the growth of the vegetables in the greenhouse.  Using air conditioners in your greenhouse is not the best practice because what conditioners actually do is that they reduce the moisture content in the growing environment.  It is advisable to use evaporative air coolers in the greenhouse instead.

Growing Herbs in a Greenhouse

A greenhouse offers the grower the opportunity to be the one in control of the growing environment, this makes it possible and also convenient to grow an herb garden successfully.  An adequate supply of moisture is needed for successful cultivation.  You may use a sprinkler system with fine hose such that water is supplied in droplets and the proper moisture level of the growing environment is maintained.  The most commonly grown herbs in a greenhouse are Chives, Parsley, Basil, Mints, and Chamomile.


Growing Fruits in a Greenhouse

The most popularly grown fruit in a greenhouse is tomatoes, but this does not mean that only tomatoes thrive in a greenhouse environment.  All fruits including vines, peaches and even citrus fruits are suitable and can perfectly be grown in a greenhouse environment.  Not all varieties of grapevines require high temperature for healthy growth, there are some varieties such as the black Hamburg that grow perfectly in a cool growing environment.  The only thing about cultivating vines is that they are attention-demanding as they are susceptible to pest attacks and therefore should be closely monitored in order to ensure a perfect growing condition for them.  As the grapevines grow, some maintenance practice needs to be carried out such as spur pruning, fertilization, etc. and waterlogged soil should also be avoided. Peaches and Nectarines are also very suitable for cultivation in a greenhouse but the right variety should be carefully selected.  This is because some varieties of Peaches such as Hale’s early require the presence of another variety nearby in order to carry out pollination successfully. A suitable variety of Nectarines for greenhouse cultivation is the Pineapple.  Hand pollination can be done for the successful pollination of fruits that do not self-pollinate.  It is also interesting to know that citrus fruits such as oranges and lemons can be successfully cultivated in the greenhouse.  The issue here is that they take almost 10 years before they start producing fruits when you grow them from seeds but the patience of growing them in a greenhouse will eventually pay off.  Ensure that the right environmental condition is created in the greenhouse, the citrus fruits usually need a temperature of about 50 – 55ºF when the outside temperature is about 4 – 5ºC.  With a little effort every now and then to keep the right growing environment, the fruits are bound to propagate successfully.