Mexican heather
Also known as
False heather, Elfin herb, Hawaiian heather, Cuphea
Keep this plant’s care guide close at hand.
Get the appAbout Mexican heather
Cuphea hyssopifolia, commonly known as Mexican heather, is a compact, evergreen subshrub prized for its fine texture and continuous bloom in warm conditions. Typically 12–24 inches (30–60 cm) tall and wide, it forms a dense mound of tiny, glossy, lanceolate leaves that resemble true heather. Small star-like flowers in shades of lavender, purple, pink, or white appear prolifically from spring through fall, and nearly year-round in frost-free climates. The nectar-rich blossoms attract bees, small butterflies, and other beneficial pollinators. Adaptable and heat tolerant once established, it prefers well-drained, moderately fertile soil and regular moisture without waterlogging. In the landscape it serves as an edging plant, low hedge, or groundcover, and it thrives in containers where its floriferous habit is on full display. Light pruning keeps it tidy and encourages branching. In cooler regions it’s grown as an annual or overwintered indoors in bright light. Hardy outdoors in USDA Zones 9–11, it may suffer damage from frost but often rebounds if roots are protected.
Taxonomy
Properties & Requirements
How to care for Mexican heather
Water
Keep soil evenly moist but never soggy. Water thoroughly when the top 1–2 inches (2.5–5 cm) of soil feel dry, allowing excess to drain freely. In containers, avoid letting the pot sit in a saucer of water. Expect more frequent watering during hot, windy spells and less in cool, short‑day periods. Outdoors, a light mulch helps moderate moisture and temperature. Reduce watering in winter indoors, letting the top layer dry a bit more between cycles while preventing complete dryness at the root zone.
Light
Provide full sun to bright, filtered light. Outdoors, aim for at least 6 hours of direct sun daily for best bloom; in very hot climates, give light afternoon shade to prevent leaf scorch and prolong flowering. Indoors, place near a south or west window with strong, unobstructed light. If natural light is marginal, supplement with grow lights for 12–14 hours daily. Insufficient light leads to lanky growth and sparse flowers; increase light gradually to avoid shock.
Nutrients
Feed lightly but consistently during active growth. Mix a balanced, slow‑release fertilizer into the soil in spring, then supplement container plants with a half‑strength, balanced liquid feed every 4–6 weeks through late summer. Avoid high‑nitrogen formulas that promote excessive leafy growth at the expense of flowers. Flush containers with plain water monthly to prevent salt buildup. In climates with frost, stop fertilizing 6–8 weeks before first freeze to reduce tender growth; resume feeding when vigorous growth restarts in spring.
Temperature
Ideal temperatures are 65–85°F (18–29°C) with warm days and mild nights. Cuphea hyssopifolia is frost‑sensitive; growth slows below 55°F (13°C) and foliage can be damaged by light frost. Protect or overwinter indoors where lows regularly drop below 40–45°F (4–7°C). Short heat waves above 95°F (35°C) are tolerated if soil moisture is consistent and afternoon shade is provided. Avoid cold drafts indoors and acclimate plants gradually when moving between indoor and outdoor conditions.
