Annual
Ranunculus (Persian Buttercup)
Ranunculus asiaticus · Ranunculaceae
Also called: Persian Buttercup, Turban Buttercup, Florist's Ranunculus
Ranunculus (Persian Buttercup) (Ranunculus asiaticus) is a moderate-water annual well suited to Tucson and the low desert. It grows to 12-18 in tall by 6-12 in wide, with a moderate growth rate.
Ranunculus (Persian Buttercup) at a glance
- Water use
- Moderate (established)
- Sun
- Full sun during the cool season; light afternoon shade helps as spring warms.
- Mature size
- 12-18 in tall by 6-12 in wide
- Growth rate
- Moderate
- Bloom
- Red, pink, orange, yellow, white, purple, and bicolors; full, multi-petaled rose-like blooms, Late winter into spring (roughly Feb-May) in the low desert
- Cold hardiness
- Tolerates light frost once established but tender shoots can be nipped by hard freezes; heat-intolerant and goes dormant/dies back as temperatures climb into the warm season.
- Soil
- Rich, well-drained soil amended with compost; excellent drainage is essential to prevent corm rot. Neutral to slightly alkaline pH is fine for Tucson with organic amendment.
- Native range
- Eastern Mediterranean, Southwest Asia, Northeast Africa
- Best used as
- Cut flowers (long-lasting, florist favorite), Cool-season color beds, Containers, Mixed spring borders
- Wildlife
- Flowers offer some nectar to bees; the irritant chemistry makes it relatively deer/rabbit resistant.
- Toxicity
- Toxic to dogs, cats, and horses (ASPCA): contains protoanemonin, an irritant causing drooling, vomiting, diarrhea, and oral/skin irritation; sap can irritate human skin as well. Keep away from pets and children.
How to grow Ranunculus (Persian Buttercup) in Tucson & the low desert
Watering
After planting corms, water in well and keep soil lightly moist (not soggy) until shoots emerge; once growing, water about every 3-5 days, keeping evenly moist through bloom. In Tucson plant pre-soaked corms in fall (Oct-Nov) or late winter (Feb-March); overly wet soil before sprouting rots the corms.
Fertilizer & nutrients
Amend bed with compost and a balanced or bloom fertilizer at planting; feed every 2-3 weeks with a balanced or higher-phosphorus liquid fertilizer through the growing and blooming period.
Pruning & care
Deadhead spent blooms to extend flowering. Foliage dies back after bloom in late spring; corms can be lifted and stored dry, but most Tucson gardeners treat it as an annual and replant.
Notes
Plant pre-soaked, claw-down corms in fall or late winter in well-drained Tucson soil for a showy late-winter-to-spring display and outstanding cut flowers. Keep soil from staying waterlogged before sprouting to avoid rot; treat as a cool-season annual and replant each year.
Sources: ASPCA Toxic and Non-Toxic Plants (Buttercup / Ranunculus); University of Arizona Cooperative Extension and Tucson low-desert planting calendars; Missouri Botanical Garden Plant Finder