Plant Spacing

Marijuana Horticulture

by Jorge Cervantes

When light shines on a garden, the leaves near the top of pants get more intense light than the leaves at the bottom. The top leaves shade the bottom leaves and absorb light energy, making less light energy available to lower leaves. If the lower leaves do not receive enough light, they will yellow and die. Tall six foot plants take longer to grow and have higher overall yields than shorter four-foot plants, but the yield of primo tops will be about the same. Due to lack of light, the taller plants have large flowers on the top three to four feet and spindly buds nearer the bottom. Tall plants tend to develop heavy flower tops whose weight the stem cannot support. These plants need to be tied up. Short plants better support the weight of the tops and have much more flower weight than leaf weight.

At least 99 two week old seedlings or clones can be huddled directly under a single 400-watt HID. The young plants will need more space as they grow. If packed too closely together, plants sense the shortage of space and do not grow to their maximum potential. Leaves from one plant shade another plant’s foliage and slow overall plant growth. It is very important to space young plants just far enough apart so their leaves do not touch or touch very little. This will keep shading to a minimum and growth to a maximum. Check and alter the spacing every few days. Eight to sixteen mature females three to four months old will completely fill the space under one 1000-watt HID.

Plants can absorb light only if it falls on their leaves. Plants must be spaced so their leaves do not overlap too much. Yield increases very little when plants are crowded. Plants also stretch for light, which makes less efficient use of intense light.

best number of plants per square for is often a matter of experimenting to find the magic number for your garden. In general, each 40-inch-square space will hold from 16 to 32 plants.