Learn how to plant, grow, and care for snapdragon flowers
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Snapdragons are favorites in our flower garden. Their spiked flowers come in many bright colors and mingle well in the garden. They’re easy to grow from seed, bloom in the cooler weather of spring and fall, and can even tolerate light frosts. Learn how to plant, grow, and care for snapdragons.
About Snapdragons
Snapdragons (Antirrhinum majus) are colorful spiked beauties that are generally cool-season flowers that bloom reliably. They are cut-and-come-again flowers, and they’re easy to start from seed or buy at the garden center in spring. With almost every color combo imaginable, snapdragons fit any aesthetic and grow well in containers.
Though technically tender perennials hardy in USDA zones 8-11, gardeners in other zones treat snapdragons as annuals. That said, breeders have developed many varieties that do well right through the summer.
They are categorized into four groups based on their temperature and daylight preferences. Group 1 and 2 snapdragons do well in the shorter days and cooler temperatures of spring and early autumn. In contrast, Group 3 and 4 snapdragons don’t mind the heat and longer midsummer days and will reliably bloom right in the hottest part of the year.
Snapdragons bloom on tall stalks and open from the bottom first. Some varieties can reach 4–5 feet tall. They are fantastic cut flowers and, with proper harvesting, will last for a week or more in the vase.
Planting
Snapdragons are easy to start indoors from seed but take quite a while to be ready for transplanting. When planting them out in the garden, choose a spot in full or partial sunshine with fertile, well-drained soil. They aren’t picky about soil type but will do best with a near-neutral soil pH.
Snapdragons are one of the earliest seeds you’ll start in preparation for spring, so don’t forget about them. If you did let the time slip by, they’re easy to find at garden centers in four packs. Choose small, thick-stemmed plants that have not yet started to bloom.
When to Plant Snapdragons
Snapdragons can tolerate some cool weather and are even frost-tolerant after their seedling stage. As long as the soil has begun to warm, they can be transplanted outdoors several weeks before the last frost.
Transplant snapdragons out into garden beds when the nighttime temperatures are hovering around freezing. Try to avoid a hard frost, but if the thermometer touches 32℉, they’ll be fine. Of course, they can also be planted outdoors later when you get around to planting other flowers and vegetables.
How to Plant Snapdragons
- If you grow snapdragons indoors, sow 8–10 weeks before planting them outdoors.
- Use soil blocks or cell trays filled with premoistened seed starting mix.
- Sow 1–2 seeds per cell or one per soil block, leaving the soil right on the surface but pressing it lightly to make good contact with the soil. Snapdragons need light to germinate, so don’t bury them.
- To preserve humidity, cover the trays with a humidity dome or plastic wrap and place them in a warm, bright location.
- Snapdragon seeds commonly take as long as two weeks to germinate. During the wait, check the moisture level to ensure they haven’t dried out.
- Once they’ve germinated, remove the humidity dome and place them under bright light. They get leggy quickly if not given enough light. A grow light for 12 hours per day works well.
Tip: Snapdragon seeds are tiny and charcoal in color, making them nearly impossible to handle. I use the toothpick method.
- Pour your snapdragon seeds into a small glass bowl or jar lid.
- Dip the end of a toothpick into the water, then touch it to the seed. The seed will stick to the toothpick, which you can then pick up and transfer to the soil.
- Gently wipe the seed off on the soil surface, then use the toothpick to lightly press the seed down into the soil where it will stick.
- The Potomac series is a Group 3-4 snapdragon loved by flower farmers for its long, dense stems full of blooms. Many colors are available, including white, red, orange, yellow, pink, and bicolor blooms. ‘Potomac Appleblossom’ is one of my favorites every year.
- Avignon series snapdragons are Group 2 cool-season performers, although they are more tolerant of heat than other Group 2 snaps. Sturdy stems and bright colors make a splash when not much else is blooming in the flower garden.
- The Chantilly snapdragons are Group 1-2 flowers with a unique open face instead of the typical closed bloom. They are quite stunning, and easy for pollinators to access, but are best grown in the cooler months.
- Snapdragons in the Madame Butterfly series are double-petaled, sometimes called azalea-type snapdragons. They have a puffy or fluffy appearance and are a Group 3-4 performer.
Andy Wilcox
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One of my new garden flowers. The deer have not tried to eat them, Yet... I can't grow much anymore because of the deer and was glad to find that they didn't like these so far.
