Snapdragon cut flower varieties compared for early Northeast harvests

What to take away

For early Northeast harvests, cut flower variety selection should start with Group 2 snapdragons such as Potomac and Sonnet because they flower under cool short days.
Group 3 types such as Rocket and Madame Butterfly add stem length and heat tolerance but usually need 10 to 21 more days than Group 2 under the same sowing date.
In zones 5-6, sow mid-February to mid-March indoors and transplant under low tunnels to hit late May and June cuts.
Match variety to tunnel climatechoose Group 2 for unheated tunnels and Group 3 for tunnels that warm quickly in May.
Stem quality and cold tolerance trade off; Rocket gives strong stems but slower early growth than Potomac.

Snapdragon groups and bloom time

Snapdragons are cool-season annuals, and their flowering groups reflect temperature and daylength needs rather than a single fixed calendar. The genus Antirrhinum includes species and hybrids grown for cut flowers, and temperature and sowing requirements shape group selection.

Group 2 types initiate flowers under cooler conditions and shorter days. Group 3 snapdragon types wait for longer days and warmer air, which is why they are often scheduled after the first spring flush. In Northeast zones 5-6, that difference decides whether a variety is cut in late May or late June.

Early variety comparison table

The table below compares snapdragon cut flower varieties and series by group, days to bloom from sowing, stem length, and cold tolerance. Treat the day ranges as planning windows from seed catalogs; tunnel temperature and light shift them.

Group

Sonnet: Group 2
Potomac: Group 2
Rocket: Group 3
Madame Butterfly: Group 3
Chantilly: Group 3 or 4
Opus: Group 3 or 4

Days to bloom from sowing

Sonnet: 90-100
Potomac: 90-100
Rocket: 100-110
Madame Butterfly: 100-110
Chantilly: 110-120
Opus: 100-110

Stem length

Sonnet: 24-30 in
Potomac: 36-48 in
Rocket: 30-36 in
Madame Butterfly: 24-30 in
Chantilly: 36-48 in
Opus: 36-48 in

Cold tolerance

Sonnet: Good
Potomac: Good
Rocket: Moderate
Madame Butterfly: Moderate
Chantilly: Lower
Opus: Moderate

Best Northeast use

Sonnet: Early tunnel cuts
Potomac: Main early crop
Rocket: Mid-season stems
Madame Butterfly: Ruffled market stems
Chantilly: Late spring to summer
Opus: Summer succession

Snapdragons are often started indoors 6 to 8 weeks before the last frost for early bloom, according to the Antirrhinum majus overview. That indoor window is shorter than the full days-to-bloom range because the plant continues growing after transplant. For early snapdragon varieties, Group 2 types are the first choice.

Northeast sowing and cold protection

For zones 5-6, sow mid-February to mid-March. Northeast cut flower growing depends on sowing date and tunnel protection. If the sowing date is still open, the page on when to start snapdragons for early cut flowers gives the 8-10 week indoor schedule for zones 5-6.

Low tunnels and row covers can protect transplants from frost without heated greenhouses. Season extension techniques such as low tunnels and cold frames are standard for Northeast cut flower growers who want early harvests.

Stem quality and market expectations

Stem length and stem strength decide whether a snapdragon sells as a cut flower or gets composted. Group 3 types often produce longer stems, but they need warmer nights than Group 2 types. Florists and market customers usually prefer straight stems with at least 24 inches of usable length. A shorter stem can still work in mixed bouquets, but it earns less per bunch.

A stem that snaps in the cooler is not a cut flower; it is compost.

Example: two sowing dates for zones 5-6

Sow Potomac indoors on February 15 at 60-65°F.
Transplant under a low tunnel on April 1, about six weeks later.
Cut the first Potomac stems in late May to early June.
Sow Rocket on March 1 for a second flush that reaches market in mid-June to early July.
Keep row covers handy for nights below 28°F.

Common questions

Which snapdragon group is best for unheated tunnels in zones 5-6?

Group 2 types like Potomac and Sonnet handle cool nights better than Group 3. Start with them for the first cut.

How much later do Group 3 snapdragons bloom than Group 2?

Under the same sowing date, Group 3 types typically add 10 to 21 days. Warmer tunnels can narrow that gap.

Can I grow snapdragons for cut flowers without a greenhouse?

Yes. Start indoors under lights, then use low tunnels or row covers after transplant. This works for zones 5-6 with a mid-February to mid-March sowing.

What stem length do florists expect?

Most wholesale and market florists look for 24 to 36 inch stems. Potomac and Rocket meet that range; Sonnet is shorter.