Place in full sun Start seeds 6 to 10 weeks   indoors before last frost for a head start. Plant seeds in well-drained soil any time after last spring frost For thin plants, plant 8 to 10 inches apart Allow oregano to grow about 4 inches and then pinch or trim lightly to encourage a denser and bushier plant. Plants will grow 1 to 2 feet tall and spread about 18 inches Harvest leaves as you need them.