Spacing of Plants in Hydroponics

All living things need space in which to live, grow and reproduce and plants are no exception to this rule. But unlike other living things that can move from place to place to make the best use of other available essentials like water, air and light, plants have to get these from the limited space in which they grow. Plants are therefore more vulnerable to deprivation of essentials if they are not provided enough living space. Therefore it is important in hydroponics cultivation as in conventional cultivation to carefully assess the space your plants will need and plan ahead keeping in mind their increasing space requirements as they grow.

Spacing of plants is an important aspect that needs to be carefully considered and properly addressed for successful hydroponics cultivation. In the event of plants being grown too close to one another, they will most likely receive less than the required amount of light. Depending on how close they are grown they may even receive less air than they require for normal growth.

Space Requirements

When the plants are just seedlings or cuttings they can be grown in close proximity, but as they grow their space requirements will increase and they will need to be moved or thinned out. In farms and gardens, this is achieved by “culling” the smaller or weaker plants thus making space for the stronger and more aggressive plants to thrive in. With more “living space” now available for the remaining plants, they can more intensively utilize the available area for healthy growth. More area for growth means more air flow to prevent mildew and more light for photosynthesis.

Benefits of Spacing

A number of studies conducted in India on flower yielding plants grown for essential oils such as Rosa Damascena have demonstrably established the growth enhancing benefits of spacing, pruning and growth hormones. The results of these tests conducted in the 1980s have shown that pruning and spacing can substantially boost flower yield; 18% to 37% increase was recorded in the experiments. It was also observed that plants treated with a low dose (50ppm) with some type of hormone solution containing auxins or cytokinins
also responded with higher total yields.

This study has demonstrated that yields can be increased with proper spacing and use of some type of growth promoter. But how much space should be allowed between plants for the best results? The rule of thumb is that for plants less than three feet tall, each plant should be minimum 18 inches apart and a maximum of 30 inches apart. For anything more than this amount of space, the law of diminishing returns sets in.

Tips for Starting out Plants

The following are some tips for preparing and planting your crop:


1. Plant cuttings right away on arrival. Plan ahead; don’t wait for the cuttings to arrive and then prepare for transplanting. You will waste valuable time getting things into place; meanwhile the plants and the cuttings will begin to loose vigor and wilt. Keep your soil, growing media, etc. ready at hand.

2. Smokers would do well to thoroughly wash their hands or use latex gloves.

3. Make sure your plants are adequately spaced. Plants grown too close to one another are weaker and more likely to fall prey to a host of diseases besides being less resistant to pests. Weaker plants are slower to grow and reach maturity; they yield less fruit or flowers.

4. Cuttings should be exposed to weak or diffused light before being introduced to full HID lighting. The lights should also be positioned not less than 3-4 feet above the new plants or seedlings.

5. Begin on a regular feed program at the earliest and keep to the manufacturer’s recommended level for new cuttings. Formulas used should contain the nitrogen (N) as the nitrate form of nitrogen and not urea or ammonia.

6. Night temperatures should ideally be maintained between 68 deg F (20 deg. F) to 80 deg F during the day. Extremes of temperature cause much harm to plants especially at the starting phase.