Larkspur Cut Flower Production in Utah Nick Volesky and Melanie Stock
Overview
Larkspur is an annual crop that provides vertical structure, height, and balance to floral arrangements. Stems also dry well, making them ideal for dried floral designs and other products. The name "larkspur" refers to the distinctive spur-like structure on the back of the flowers. Preferring cooler temperatures, seeds can be sown in either spring or fall. Each plant produces a single primary stem, along with secondary side stems that may also be of harvestable quality. Larkspur is an excellent choice for early high tunnel production, and harvest can be staggered by pairing production with an unprotected field crop.
conditions include average, well-drained soil with partial to full sun. Performing an initial soil test and incorporating compost or organic matter prior to planting is recommended for establishment and longterm plant health. USU’s Analytical Laboratories (USUAL) perform soil tests, with pricing and sampling instructions available on their website.
Species, Series, and Colors
Consolida ajacis and Consolida regalis are the two most common species grown for cut flower production. C. ajacis is taller, more robust, and features densely clustered flowers, often informally referred to as "giant" or "rocket” larkspur (Figure 1). In contrast, C. regalis is shorter and produces looser flowers with a more airy, wild, single-bloom appearance, sometimes called "forking" or "cloud" larkspur. Both species possess desirable design attributes that are highly marketable to florists. Larkspur seeds are often sold by series, which are cultivar groups of varying colors that are bred and marketed together. Utah State University (USU) trialed three colors for each Cannes, Fancy, and QISTM series (C. ajacis) in 2023 and 2024. The study results are detailed at the end of the fact sheet.
Site Preparation
As a direct-sow, annual crop, site selection is important. Direct sowing and initial germination can be challenging when soil conditions are too dry or wet. Competition from germinating weeds also limits survival. Optimal
Figure 1. High-tunnel-grown larkspur (Consolida ajacis) ready for harvest with a quarter to one-third of the florets on the raceme open.
Utah State University Extension | August 2025 | Peer-Reviewed Fact Sheet | CutFlower/01
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