Giant Imperial Mix
What's special about Giant Imperial Mix
Tall 4-ft double-flowered spikes in blue, pink, salmon, white, purple. The florist standard.
Growing this variety
Giant Imperial Mix follows the same growing basics as Larkspur. Variety-specific maturity above; everything else below applies to the whole Larkspur family.
Germination
Spacing & depth
How to plant
Sow directly in fall or very early spring — larkspur wants cold soil to germinate. Chill seed in the freezer for a week before sowing if spring-planting. Once up, plants tolerate light frost and bloom on 3–4 ft spikes.
Pre-sow treatment
Chill seed in freezer 1 week, or sow outdoors in fall to cold-stratify naturally.
Grower's tip
Basically an annual delphinium for hot summers. Excellent fresh or dried cut flower.
Soil preferences
Well-drained garden soil. Native/wildflower species prefer lean soil; cutting flowers prefer richer beds.
6.0–7.0
Work 1 in of compost into beds before sowing. Skip nitrogen fertilizer on wildflowers — it favors foliage over blooms.
Watering
1 in per week during establishment, drought-tolerant once rooted for most species.
Deep, infrequent soakings at the base. Overhead water on ornamentals promotes botrytis and rust.
Overwatered: rotted crowns, mildew, floppy stems. Underwatered: small blooms, curled leaves, quick fade.
Prefers top-watering — Top-water at the base in the morning. Overhead water batters open flowers and spreads botrytis on tightly-packed blooms.
Temperature tolerance
60–80°F (16–27°C) ideal for most annuals
50–65°F (10–18°C)
Cool-season annuals (larkspur, poppy, snapdragon) tolerate light frost; warm-season annuals (zinnia, cosmos, marigold) are frost-tender.
Container growing
Possible with the right cultivar
8–14 in (20–35 cm) wide
Compact and dwarf types do best in pots; tall cutting flowers need staking.
Succession planting
Sow cutting flowers (zinnia, cosmos, sunflower) every 3 weeks through midsummer for continuous cut stems.
Detailed harvesting
Cut in early morning when stems are turgid. For cutting varieties, harvest when the bud is just showing color and 1–2 outer petals have opened.
Post-harvest storage & preservation
Immediately re-cut stems underwater and place in clean cool water for 4 hrs before arranging. Petals can be dried on screens for potpourri or crafts.
Culinary, medicinal & other uses
Cut flowers, dried arrangements, pollinator habitat, edible garnishes (borage, nasturtium, calendula, viola).
Medicinal or traditional uses are shared for interest only — this is not medical advice. Consult a qualified professional before using any plant medicinally.
Seed saving
Mostly insect-pollinated (outcrossing).
For pure strains, isolate 150–800 ft or bag heads. Wildflower mixes are meant to cross freely.
Stop deadheading favorite blooms; let heads dry brown and rattling on the stem, then collect into a paper bag.
Your zone's planting calendar
Pick your USDA hardiness zone and we'll estimate the key dates for larkspur in your area. These are regional averages — always check your own last-frost forecast before sowing.
My Giant Imperial Mix Larkspur notes
Giant Imperial Mix Larkspur seeds on hand
Track packets and loose seeds you already have. Private to your account.
Par level — leave at 0 for no alert. Anything below par shows on Seed Starting and your shopping list.
From your kitchen — grow larkspur from what you already have
Deadhead less. Let the best blooms fade and set seed on the plant — that's your next year's packet.
- 1Mark 2–3 of your favorite flowers with a bit of yarn and stop deadheading them.
- 2Wait until the seed head or pod dries fully on the plant — brown, papery, and rattling.
- 3Cut whole heads into a paper bag on a dry day; shake or rub to free seed.
- 4Sieve out chaff and store cool and dry in a labeled envelope.
Storage: 2–5 years for most flower seed.
Order more seeds
Running low? Reorder from one of these seed stores.
Loading…