Dig a 4-to-6-inch-deep trench that is as long as your tomato seedling is tall.
Remove the seedling from its pot and gently massage the rootball apart. Snip off the leaves on the lower portion of the stem, leaving two to four sets of leaves at the top of the stem to ensure enough leaf surface for photosynthesis.
Lay the plant horizontally in the trench. Backfill with soil, gently bending the stem of the tomato upward so the leaves remain above ground. Don't worry, your "Leaning Tower of Pisa" will straighten as it grows.
Place a cage around the plant or stake it immediately after planting. If you wait until later, you may disturb your tomato's growing root system.
For more information on growing tomatoes, see our Tomato Growing Guide.
Or watch a video about planting tomatoes.