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Grow Under Fluorescent Lights


Grow Under Fluorescent Lights

The fluorescent lights will provide sufficient light for growth during any month of the year, however another requirement of plants is sufficient warmth. The garage will provide protection against much of the temperature fluctuations throughout winter, but not sufficient for germinating and growing seedlings nor for the propagation of cuttings. 

There are two alternatives available. Firstly an electric heater with a thermostat control. One of these will cost roughly �15 new or a fiver secondhand. The second alternative is a paraffin heater - this is not recommended from a safety (especially within a garage) or efficiency view point. 

picture of usable electric heater
A typical electric heater with thermostat

The energy efficiency of the electric heater can be increased by partitioning that area of the garage which is to be heated, although this is by no means necessary.

Position The Fluorescent Lights

In order to mimic natural sunlight, the fluorescent lights should be between 18 to 24 inches above the top of the plants. The odd inch or two will not make much difference, although young seedlings will be 'burnt' if the lights are too near.

As a guide, a 6 foot fluorescent light will provide a growing area of 6 foot long by 1 foot wide. The more fluorescent lights, the larger the growing area.

Usage of the Lights

If the above advice is taken, plants under the fluorescent lights can be treated exactly as normal. Heat can be varied using the heater's thermostat as required.

Suggested Uses
The principal use is to enable the raising of seedlings and the propagation of cuttings a month or so earlier in the season than would normally be possible. 

For example, geranium seeds are normally sown in January or February. Using fluorescent lights, it is possible to sow them in early December, and place them under the fluorescent lights when the seedlings emerge. When the weather is kind enough to allow planting outside, the plants will be one or two months further advanced than conventionally sown seed. Another prime example is sweet corn. These can be sown under fluorescent lights a month earlier than normal. In the case of sweet corn, the lights should be on for 12 hours and off for 12 hours - sweet corn grow when it is dark.

It is also possible to sow seed in mid-October, raising the seedlings under the fluorescent lights until early January. At this point, the plants will be large enough to provide three or four cuttings for raising under the lights. In this manner, one F1 seed will provide three or four plants. 

One word of warning! Remember that seedlings and cuttings will need more space as they grow. Plan for this space requirement taking into account the growing area you have available.