Tomato (Greenhouse Production)

Growing Tips: Tomato (Greenhouse Production)

Quick Reference:

Broadcast in flats and cover with 1/8 to 1/4 inch fine soil spaced 1/2 to 3/4 inches apart. Germination: 8 to 14 days. Transplant seedlings to 3 to 5 gallon containers for greenhouse production. Separation between plants 2 feet. Provide plants support with tomato cages.

When and where to plant:

Standard tomato varieties that are grown outdoors in warmer climates can only be grown in a greenhouse in Alaska because standard tomatoes require warm soils and night temperatures in excess of 55 degrees to set fruit. In late winter fill containers that have drainage holes with sterilized soil, broadcast seed on the surface, cover lightly with soil and firm soil over seed. Water well and do not allow the containers to dry out during the germination period. After the seedlings have their first true leaves, plants will be approx. 2 to 3 inches tall, they should be transplanted to individual plastic pots. Use a pot large enough to allow plants to grow until the greenhouse will be opened. When the greenhouse is warm transplant seedlings to large 3 to 5 gallon containers with drainage holes filled with fertile loam that has been enriched with plant food and organic matter. Water well, tomatoes transplant easily.


Tomatoes are shallow rooted and require uniform moisture. Water thoroughly as the soil begins to dry out and apply a liquid solution of plant food high in phosphorus every two weeks. Indeterminate plants grow tall and need to be staked or supported with wire tomato cages. Vibrate plant stems when flowers are fully open to pollinate for a good fruit set. On cool nights the greenhouse will need supplemental heat.


Pick when fruit color is fully developed.