In order to have the healthiest, most productive Marmande tomato plants, it's best to start the seeds indoors before transplanting them into the outdoor garden. Using peat pots filled with a quality potting soil, plant one to two seeds in each pot at a depth of 1/8 to 1/4 inch.
Once the seedlings are established and have at least two sets of full leaves, you can work on transplanting them into the outdoor garden. Prepare the soil by adding compost or transplant solution and moistening the soil. Dig a hole that is about 1 inch deeper than the peat pot holding the seedling. Place the seedling in the hole and cover with slightly moist soil, gently patting it around the base of the plant. Install a tomato cage for future support.