Nursery - Spacing Container Plants

The following is a short article on spacing container plants in nurseries and garden centers.

Spacing Container Plants

Proper spacing is important to produce high quality plants. Adequate exposure to sunlight is necessary for trees to photosynthesize at the maximum rate, supporting the maximum growth possible. Leaves are shed if they do not produce more food than is required to maintain them. The leaves most prone are those in heavy shade on the lower trunk. Leaves and small stems along the stem are critical to developing caliper. Caliper development is crucial to developing a strong trunk that doesn't need to be staked and for growing a plant to the desired size. In addition, plants that are too close often look great as a block but when individual plants are pulled they have one-sided or sparse canopies. During production plants should not be closely spaced for any longer than is necessary. As a general guideline no more than 3 weeks to prevent canopy problems and less, especially if rainy or humid, to avoid the disease problems. Additional benefits are ease of spraying, pruning, and training leaders.

How much space is adequate? Check your plants several times throughout the day to see the shade pattern and adjust your space accordingly. Plants intended to grow in full sun (not under a shade structure) will do best with full sun or at least 6 hours of sunlight. During the hottest part of summer some midday shade can be beneficial but that is not the type of shade created when plants are too closely spaced. Consider that 15 gallon pot-in-pot socket pots are typically spaced on 5' centers and 25 gallons at 6' centers.

Source: Spacing and Pruning Trees in Field Nurseries. UT Pub. PB 1458.