5871- Flax, Golden. 2-2½ ‘ tall plants with nice blue flowers. Good yield of flax seeds. Direct seed outdoors, covering them 1/4- to 1/2-inch-deep. Water gently if the soil starts to dry out before germination, which takes about 10 days. Seedling flax plants quickly develop a good root system and need watering only if the weather is unusually warm, dry or windy.