It has been a popular trend to grow marigolds in greenhouses during the summer months. That's because a dry and hot season is appropriate for growing marigolds. There are different types of marigolds available. They vary in their size, the type of flower and their habits of growth. 6 inches is its minimum size while 3 feet is its maximum. The African and the French marigolds are among the common ones. The triploid type is another one.

The seeds used for producing marigolds should be of very good quality. From just one ounce of seed, seedlings produced should be maximum. F1 Hybrid is probably the best choice. If the seeds are to be kept over two seasons or more then their environment should be cool, dry and dark. It should be insect and rodent free. The plugs of marigold should be purchased from the propagators. The size of the plants should be such that transplanting can be done. The seedlings shouldn't be overgrown or undergrown. Its roots must be big and white in color. You should confirm that the seedlings don't have any diseases and pests.

When three or four leaves appear on the seedlings then the plugs of marigolds can be transplanted. The plugs can get stunted if they remain for a longer duration in the greenhouse itself. Immediately after the transplant, watering should be undertaken in a thorough manner. In order to grow marigolds temperature should be maintained properly. During the night, temperature should be 600 to 650 F. For plants of high quality the temperature during the day should be about 720 F. temperature can be kept at 640 F at night in the beginning and later be brought down to 600 F.

You need to wait for about 10 days before using fertilizers. The roots should reach the container's bottom or side. When fertilization begins it should be in liquid form. The light needed by marigolds is the maximum possible. Hence, they should be placed in areas where bright light is received. Its growth should be managed and controlled. According to the type the growth of marigolds will vary. Thus, keeping these few points in mind, surely growth of marigolds can be undertaken.