plant out
To put (a plant) into the ground outside, from a greenhouse or a plant pot.
plant out: moving seedlings from nursery to field
To plant out is to transplant a young plant, seedling, or rooted cutting from protected growing conditions, such as a greenhouse, cold frame, or propagation tray, into permanent outdoor soil. This is the final stage before a plant reaches its production environment, whether that is a vegetable plot, orchard, or commercial field. The term distinguishes this operation from sowing seed directly into the ground or from potting up, which moves a plant into a larger container.
The timing of planting out depends on crop type, local frost risk, and desired harvest window. For example, tomato and pepper seedlings grown indoors are typically planted out 6 to 8 weeks after germination, once they have developed true leaves and the risk of frost has passed. Brassicas may be started in a seedbed and transplanted into their final positions when 4 to 6 inches tall. Hardening off, the gradual exposure of plants to outdoor conditions over 7 to 10 days before planting out, reduces transplant shock and improves establishment.
Practical constraints and failure modes
Successful planting out requires soil temperature, moisture, and nutrient conditions suited to the crop. Cold, waterlogged, or compacted soil increases transplant failure and disease pressure. Root damage during extraction and insertion delays recovery; careful handling of root-bound plants and correct planting depth minimize this risk. Weather shock, particularly sudden temperature swings or high winds immediately after planting out, stresses young plants and increases wilt or mortality, especially in high-value crops.
Commercial operations use mechanical transplanters for high-volume planting out of uniform crops such as vegetables, tobacco, or bedding plants. These machines set plants at precise spacing and depth, improving consistency and reducing labor compared to hand planting. Smaller operations, nurseries, and specialty crops rely on hand planting, which is slower but allows flexibility and better attention to plant quality and soil conditions.
Planting out differs from direct seeding because seedlings establish faster and flowering or fruiting begins sooner, shortening the production cycle. It is essential for crops with small seeds, long juvenile periods, or high seed cost, and for achieving season extension in cool climates. The term is common in temperate-zone horticulture and market gardening, less so in tropical systems where field sowing is more economical.