Snapdragons are cool-season flowers with tall spikes of ruffled blooms. UF/IFAS Extension notes they are grown as cool-season annuals, though they may live as short-lived perennials in zones 7 to 11. Plants range from about 6 inches to 3 feet tall depending on cultivar. This page covers when to plant, spacing, pinching and the rust problem.
Snapdragon at a glance
| Type | Flower |
|---|---|
| Season | Cool-season |
| Sun | Full sun to part shade |
| Plant spacing | 8 in |
| Row spacing | 8 in |
| Per square foot | 1 |
| Seed depth | At surface |
| Days to maturity | Start seed 6–8 weeks before transplanting |
| How to start | UF/IFAS says to set plants out after the last frost, and that fall planting gives winter color in zones 9A to 11B. |
| Water | 1 in per week |
These are the same numbers our plant spacing, square foot and harvest date calculators use. See every crop in the plant database.
When to plant snapdragon
UF/IFAS says to set plants out after the last frost, and that fall planting gives winter color in zones 9A to 11B. Start seed 6 to 8 weeks before transplanting. In zone 7, plant in April or September; in zone 8, January to March or October to December. Bloom is in spring and fall in northern zones and fall and winter in southern zones. Use the frost dates by ZIP code and planting calendar.
How to plant snapdragon
- Pick sun to part shade. Full sun to partial shade works.
- Space 6 to 10 inches apart. UF/IFAS's table lists 6 to 12 inches; use the plant spacing calculator.
- Use well-drained soil. Slightly acidic is ideal, but clay, sand, loam and slightly alkaline soils are tolerated.
- Pinch young plants. Pinch back before flowering for side growth and a fuller plant; this delays blooming.
Caring for snapdragon
Feed when second-crop flower buds appear, after cutting back spent plants to 5 to 6 nodes. The garden watering calculator can help with watering.
Companion plants
| Grow nearby | Pansies, alyssum, dianthus and other cool-season flowers |
|---|---|
| Keep apart | Hot, humid summer sites for fall-planted beds |
Snapdragons fade in heat, so plant them with flowers that carry the bed into summer. Check other pairings with the companion plant finder.
Common problems
| Problem | What you see | What to do |
|---|---|---|
| Rust | Brown pustules, yellowed leaf tissue and small flowers | Named by UF/IFAS as the main disease. Remove affected leaves and see the pest identifier. |
| Yellow leaves | Leaves yellowing | Check watering and rust. Use the yellow leaf identifier. |
Not sure what you are looking at? The plant problem identifier ranks likely causes from the symptoms you see.
When and how to harvest
Snapdragons are grown for cut or garden flowers. After a flush of bloom, cut plants back to 5 to 6 nodes and feed to encourage a second crop.
Plan your snapdragon
- Plant spacing calculator: how many plants fit your bed
- Planting calendar: sowing and transplant dates for your frost dates
- Frost dates by ZIP code: your last spring and first fall frost
- Harvest date calculator: when your crop will be ready
Frequently asked questions
How far apart should I plant snapdragons?
Space snapdragons 8 inches apart in rows 8 inches apart. In a square foot garden, plant 1 per square foot.
How deep do I plant snapdragon seeds?
Space snapdragon plants 6 to 10 inches apart and set them out after the last frost.
How long do snapdragons take to grow?
Start seed 6 to 8 weeks before transplanting; bloom comes in spring and fall in northern zones and fall and winter in southern zones.
How much water do snapdragons need?
About 1 inch of water a week, from rain and watering combined. Keep plants evenly watered; they grow in well-drained soil.
Do snapdragons come back every year?
They are grown as cool-season annuals but may live as short-lived perennials in zones 7 to 11.
Should I pinch snapdragons?
Yes. Pinching before flowering encourages side growth and a fuller plant, but it delays blooming.
What causes brown spots on snapdragon leaves?
Rust, which causes brown pustules, yellowed leaf tissue and small flowers.