Dill can be harvested about 8 weeks after sowing. At this stage the plant will begin to produce flower heads, causing the leaf production to stop. Dill will keep well in the fridge for about 3 weeks but it can be stored in the freezer in individual portions or can be dried and stored in an airtight container. The seeds are harvested by cutting the flower heads off the stalks when the seeds are beginning to ripen. The seed heads are placed upside down in a paper bag and left in a warm dry place for a week. Separate the seeds from the stems and store in an airtight container.
Dill will grow well in most soils, but prefers rich, well-drained soil. Prepare the soil by digging to a spade and a half depth and incorporate some long lasting fertilizer. For a successful cultivation, Dill requires warm to hot summers with high sunshine levels, and a place that is not exposed to high winds. Plants intended for seed for further planting should not be grown near fennel, as the two species can hybridize.
Dill seeds should be sown in mid spring, after the last frost, covering the seeds with only a fine layer of soil. Water thoroughly immediately after sowing and keep the soil moist until plants begin to sprout. The seedlings will emerge in two weeks or so, and should be thinned to 24 cm apart. Further sowings can be made during the spring and early summer to extend the harvest time. The only care required is to keep the plants weed free and to water the plants once or twice a week during dry spells.
Dill is also suited to be grown in containers. For growing outside, use normal potting compost and keep the plants well watered. For growing indoors, sow the seeds during mid autumn in 7cm pots and transplant the plants to larger pots when they are about 15 cm tall. Keep the plants on a sunny windowsill, out of direct sunlight and away from radiators. The plants will need to be supported with a stake. They will be ready for harvest about 8 weeks after sowing.