Salvia rosmarinus 'Arp' aka Rosmarinus officinalis 'Arp' (Arp Rosemary, Hardy Rosemary, Cold-Hardy Rosemary) - Herb Seeds / Plug Plants / Seedlings & Transplants

It forms a dense, upright to slightly spreading shrub typically reaching about 3–5 feet tall and wide, with fine, needle-like leaves that are gray-green to silvery-green. Like other rosemary types, the foliage is highly aromatic when brushed or crushed, releasing a strong piney-resin scent with hints of camphor and citrus.

One of its standout traits is its exceptional cold tolerance compared to most rosemary cultivars. ‘Arp’ can often survive brief cold snaps down to around 0°F (-18°C) once established, making it a popular choice for gardeners in cooler climates where rosemary is usually marginal.

In late spring to early summer, it produces small pale blue to light lavender flowers, which are attractive to pollinators like bees. In favorable conditions, it may also bloom sporadically outside this period.

It prefers:

• Full sun (best growth and strongest aroma)
• Well-drained, even poor or rocky soil
• Low to moderate watering (drought-tolerant once established)

Like most rosemary, it does not tolerate waterlogged soil well and is more likely to suffer from root rot than cold damage if drainage is poor.

Culturally, ‘Arp’ is valued both as a culinary herb (for roasted meats, potatoes, and infused oils) and as a landscape plant for hedges, borders, and xeriscaping. Its upright habit and resilience make it one of the most reliable rosemary varieties for temperate gardens.