Bok choy (Brassica rapa var. chinensis), also called pak choy, grows during the cool spring or fall seasons. The upright heads feature leafy green tops and firm white ribs with a mild flavor that complements a variety of cooked dishes. Peat pots or pellets, which break down in the soil after planting, allow you to transplant without damaging the delicate roots. Transplant bok choy in spring when night temperatures are above 50 degrees Fahrenheit, or in late summer six weeks before the first expected frost.
Set the bok choy seedlings outside in a protected area one week before transplanting. Gradually increase the plants' exposure to direct sunlight daily, but bring the plants indoors if frost is expected. This process, called hardening, prepares the seedlings for garden conditions.
Spread a 2-inch layer of compost over a garden bed and work it into the top 6 inches of soil. Select a bed that receives full, all-day sunlight and drains well so it doesn't become soggy or waterlogged.
Dig each planting hole 1/2 inch deeper than the seedling pot. Space the holes 16 inches apart in rows set 24 to 30 inches apart.
Tear the rim off the peat pot, if applicable, before transplanting. Set the bok choy seedling in the prepared hole so the rim of the pot is just beneath the soil surface. Peat pots wick moisture away from the plant's roots if the rim protrudes above the soil.
Fill the hole in with soil, firming it gently with your palms. Water the bok choy immediately after transplanting until the top 6 inches of soil are moistened so the soil can settle around the pot and roots.