How to Transplant Mustard

Sprinkle 1 cup of 16-16-8 fertilizer over every 25 square feet of garden bed in an area that receives full, all-day sun. Cover the fertilizer with a 2-inch layer of compost. Mix the compost and fertilizer into the top 6 inches of soil with a spade.

Set the mustard transplants outside in a protected area one week before transplanting, after most frost danger is past and soil temperatures have warmed to at least 40 degrees Fahrenheit. Bring the seedlings indoors if frost is expected, and return them outside when frost danger is past. Continue this process for one week before planting so the transplants can adjust to outdoor conditions.

Place your hand over the top of the pot so the mustard seedlings protrudes from between your fingers. Turn the pot upside down and squeeze the sides so the root and soil ball slides out into your upturned palm.

Dig the planting holes to the same depth as the transplant's roots, and space the holes 3 inches apart in rows that sit 12 inches apart. Set the mustard plants in the holes so they are at the same depth they were growing at previously. Fill in the holes and gently firm the soil around the base of each transplant.

Water mustard immediately after transplanting so the top 6 inches of soil is moist and so the soil settles around the roots. Continue to water about once weekly to moisten the top 6 inches of soil, supplying about one inch of water each session.