Planting Carrots Plant your carrots in rows that are 1 to 2 feet (30-60 cm.) apart. Seeds should be planted about a ½ inch deep and 1 to 2 inches (2.5 to 5 cm.) apart. When growing carrots in the garden, you’ll wait for your carrot plants to appear. When the plants are 4 inches (10 cm.) high, thin the plants to 2 inches (5 cm.) apart. You may find that some of the carrots are actually large enough to eat. When growing carrots in the garden, make sure to plant, per person, five to ten feet of row to have enough carrots for table use. You will get about one pound of carrots in a one foot row. You want to keep your carrots free of weeds. This is especially important when they are small. The weeds will take nutrients away from the carrots and will cause poor carrot development.