How to Grow Snapdragons for Cutting: The Complete Seed-to-Vase Guide
- Jane Westoby
- Jul 13
- 4 min read
Snapdragons might seem like a cottage garden staple — but don’t be fooled. These are serious cut flower performers. Once you know how to grow them properly, they’ll reward you with tall, straight stems, florist-worthy blooms, and colour from spring right through to autumn.
In this post, I’m breaking down everything you need to know about growing snapdragons from seed — including which varieties to choose, when to sow, how to pinch, and how to avoid common mistakes like bent stems or poor flowering.
Not All Snapdragons Are Created Equal
First things first: not all snapdragons are meant for cutting. Most of the seeds you’ll find in garden centres are bedding varieties — bred to stay short and compact for containers and borders. Great for pots, but useless for bouquets.
If you’ve ever sown snapdragons and ended up with ankle-height plants and stubby stems, that’s why.
What to look for instead: Always check the seed packet for stem length — you want long stemmed varieties bred specifically for cutting. Some of my favourites include:
Potomac – long, uniform summer stems
Madame Butterfly – frilly, open-faced, and flexible across seasons
Double Shot – beautiful for early and mid-summer flowering
Snapdragon Group System and Why It Matters
Snapdragons are grouped by how they respond to day length and temperature. Here’s the breakdown:
Group 1: Cool temps + short days → Best for overwintering or very early spring blooms
Group 2: Early to mid-season → Tolerates cold, blooms early
Group 3: Mid-season → Ideal for late spring to early summer
Group 4: Late season only → Needs long days and high temps — not ideal for UK growers
Pro tip: Start with Madame Butterfly if you’re overwhelmed. She’s group-flexible and flowers beautifully from spring through autumn.
When to Sow Snapdragon Seeds
Snapdragons are slow to get going — but they’re worth the wait.
You’ve got two sowing windows:
Late summer to early autumn — for early blooms next spring
Late winter to spring — for summer flowering
How to Sow Snapdragon Seeds
Snapdragon seeds are tiny, but with careful handling, they’re easy to germinate and grow into strong, healthy plants.
Use a high-quality, free-draining potting mix. Fill seed trays or small pots, pressing the soil down gently to remove air pockets.
Pre-moisten the soil before sowing—snapdragon seeds are so small they can be washed away if watered from above.
Sow thinly and evenly over the surface of the compost. If using soil blocks, a toothpick can help place the seeds accurately.
They can be covered lightly with vermiculite and mist gently to settle the seeds. ( You can also wait until after germination to add the vermiculite as it helps prevent damping off)
Place under a humidity dome or cover to retain moisture and put onto a heat mat for faster germination.
Move to a cooler, well-lit space as soon as they germinate (usually within a week or two).
Preventing Damping Off
Snapdragon seedlings can be prone to damping off (a fungal disease that kills young plants). To reduce risk:
Use plenty of airflow—a small fan or open greenhouse vents on mild days.
Avoid overwatering—let the soil dry out slightly between waterings.
Harden off seedlings by placing them outside for a few hours on mild days.
Sprinkle a little vermiculite over the top of the seedlings to hold the soil in place
Planting Out & Growing Snapdragons
Snapdragons take 100–120 days from sowing to flowering, though overwintered seedlings will bloom much earlier in the season.
Autumn-sown seedlings will flower in late winter to early spring.
Spring-sown snapdragons will bloom midsummer through to autumn.
When to Plant Out Snapdragons
Snapdragons can be planted out when they are still small. They’ll establish their root system beneath the soil, ready to take off when the weather warms.
For early spring blooms, plant in autumn or late winter with some frost protection.
For summer and autumn flowers, plant in early spring.
Snapdragons can tolerate cold but not prolonged frost or snow—so a low tunnel or fleece covering may be needed in harsh conditions.
Ideal Growing Conditions for Snapdragons
Light: Full sun to partial shade (at least 6 hours of sunlight per day).
Water: Keep soil consistently moist but not waterlogged. Water at the base to prevent fungal disease.
Fertiliser:
Apply a balanced feed every 4–6 weeks during active growth.
Once buds appear, switch to a high-potash feed (like tomato fertiliser) to encourage strong flower production.
Should I pinch my Snapdragons? (And How to Double Your Plants)
There’s a lot of chat in the flower world about whether or not to pinch snapdragons. Here’s my take:
Don’t pinch = One tall central stem, good for early weddings
Pinch = Bushier plant with more stems, slightly shorter blooms, and later flowering
🌱 Bonus tip: When you pinch? Root the tip.Pop that top into compost with a dash of vermiculite, or even into water, and it’ll root within days. Just like that — you’ve doubled your plant count.
Harvesting & Conditioning Snapdragons for the Longest Vase Life
Cut deep into the plant, rather than deadheading—this encourages longer stems and stronger regrowth.
Harvest when around a quarter to a third of the flowers are open. Cutting too early results in poor colour development and smaller blooms.
Condition stems properly:
Snapdragons are geotropic—they bend towards gravity if laid at an angle. Store them upright in deep water.
Leave in a cool, dark place for a few hours before arranging.
Snapdragons are one of the most rewarding cut flowers you can grow—highly productive, long-lasting, and available in colours to suit every bouquet. By choosing the right varieties and caring for them correctly, you can enjoy a continuous harvest from early spring through to late autumn.
Join the Snapdragon Grow-Along
If you’ve struggled with snapdragons before — or just want a little hand-holding this season — join my free Snapdragon Grow-Along.We’ll sow together, troubleshoot as we go, and get you growing florist-grade blooms in no time.
👉 Click here to join the Grow-Along Its Free to join — you just need your seeds (we’ve got some dreamy mixes arriving this season).
For more information on growing Hardy Annuals check out our blog Growing Cool Flowers
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