Companion plants for Rosemary
Rosemary blooms from March through May. It wants full sun and low water. The 8 companion pairings below each state why the pairing works.
Taking over as Rosemary finishes

Gazania
Shares full sun and low water; blooms in early summer as this one finishes; lower at 10 in, for the front of the border; both offer pollinator forage, in different months.

Blanket Flower
Shares full sun and low water; blooms in early summer as this one finishes; both are strong pollinator plants, and they feed in different months; lower at 1.5 ft, for the front of the border.

Lantana
Shares full sun and low water; blooms in early summer as this one finishes; both are strong pollinator plants, and they feed in different months; lower at 1.5 ft, for the front of the border.

Vinca
Shares full sun and low water; blooms in early summer as this one finishes; both are strong pollinator plants, and they feed in different months; lower at 12 in, for the front of the border.

White Clover
Shares full sun and low to moderate water; overlaps, then carries the display into midsummer; low at 4 in, to carpet the ground beneath; both are strong pollinator plants.

Dill
Shares full sun and low to moderate water; blooms in early summer as this one finishes; both are strong pollinator plants, and they feed in different months.

Ice Plant
Shares full sun and low water; blooms in early summer as this one finishes; low at 4 in, to carpet the ground beneath; both offer pollinator forage, in different months; they only overlap in zones 8 to 9.

Jasmine
Shares full sun and low to moderate water; blooms in early summer as this one finishes; both are strong pollinator plants, and they feed in different months; its white flowers settle the blue.