Lovage

Sow seed in spring, either in a tray to transplant later or direct into a lightly shaded bed, and thin or space the plants about 30 inches apart (spacing per University of Maryland Extension). Work compost or well-rotted manure into the planting hole and pick a spot that stays moist without waterlogging. Illinois Extension describes lovage as a large, vigorous hardy perennial growing 4-6 feet tall, and it widens to about a yard across within a few years, so it needs the room and the fertility from the start; a fairly rich, moist soil with light shade improves the quality of the leaves and keeps them tender rather than coarse.

Spread a layer of garden compost or well-rotted manure around the crown each spring as the new shoots come up. Water established plants during prolonged dry spells. Lovage does best in a rich, fairly moist soil that never dries out, and a compost mulch feeds the plant and holds that moisture in one pass, so no separate fertilizer is needed.

Lift a large established clump in spring as growth begins, split the crown into rooted pieces with a spade or knife, and replant them at the original depth in fresh, enriched soil. Lovage spreads to about a yard across and thickens over the years; division both renews a congested crown and is the reliable way to propagate a plant you already like, since seed is variable.

As the tall flower stalks rise and the greenish-yellow umbels start to form, cut them out at the base unless you want seed. Keep picking young leaves frequently to pull new growth. Lovage leaves turn bitter once the flowerheads form, and the plant pours its energy into seed instead of foliage, so removing the stalks extends the leaf harvest by weeks.

Check the celery-like leaves through summer for pale winding tunnels or blotches made by celery leaf mining fly. Pick off and destroy the mined leaves while the damage is still light rather than spraying. The larva feeds between the two leaf surfaces, so a spray cannot reach it once the mine has started, and leafminers are normally held in check by parasitic wasps anyway.

On any stalks you left to flower, cut the seed heads once they start to turn brown and hang them upside down in paper bags to finish drying, then shake the seed loose. Lovage seed shatters off the umbel as soon as it is fully ripe, and the plant self-seeds freely, so catching the heads at the brown stage saves the spice and saves you weeding out volunteers next year.

Once hard frost has knocked the leaves and flower stems down, cut the old top growth back to the ground. You can also leave the stems standing over winter and cut back in early spring, just before new growth starts. Lovage dies back and goes dormant in winter, and clearing the spent foliage removes the leafminer and leaf-spot inoculum that would otherwise overwinter in it and reinfect the new spring flush.