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ENH1285
Planting and Propagation of Snapdragons in Florida1
Heqiang Huo and Jianjun Chen2
1. This document is ENH1285, one of a series of the Environmental Horticulture Department, UF/IFAS Extension. Original publication date January 2018.
Visit the EDIS website at http://edis.ifas.u.edu.
2. Heqiang Huo, assistant professor; and Jianjun Chen, professor, Mid-Florida Research and Education Center, UF/IFAS Extension, Apopka, FL 32703.
The Institute of Food and Agricultural Sciences (IFAS) is an Equal Opportunity Institution authorized to provide research, educational information and other services only to
individuals and institutions that function with non-discrimination with respect to race, creed, color, religion, age, disability, sex, sexual orientation, marital status, national
origin, political opinions or aliations. For more information on obtaining other UF/IFAS Extension publications, contact your county’s UF/IFAS Extension oce.
U.S. Department of Agriculture, UF/IFAS Extension Service, University of Florida, IFAS, Florida A & M University Cooperative Extension Program, and Boards of County
Commissioners Cooperating. Nick T. Place, dean for UF/IFAS Extension.
Introduction
Snapdragon (Antirrhinum majus L.) belongs to the genus
Antirrhinum consisting of species in three sections (sec-
tion is a taxonomic rank below genus but above species):
Antirrhinum, Saerohinum and Orontium. e section
Antirrhinum comprises 19 diploid perennial species (Tolety
and Sane 2011). ese species are native to the western
Mediterranean region and produce relatively large owers
(Oyama and Baum 2004). e name “Snapdragon” comes
from the appearance of its owers, which resemble the jaws
and snout of a dragon (Figure 1). e word “Antirrhinum”
is derived from Greek, where anti means “like” and rrhinum
means “snout”. Furthermore, its head will open when the
ower is squeezed and snap shut when released, which
looks like a dragon jaw opening, then snapping shut.
Only snapdragons in the Antirrhinum section have been
domesticated, and their production as a garden plant dates
back to the Roman Empire (Tolety and Sane 2011). Both
Romans and Greeks thought snapdragons had magical
qualities to protect them against charms and enchantments
from witchcra, and protection from illness or poisoning
(Tolety and Sane 2011). Snapdragons were also planted near
gates as the guardians of European castles. Wild varieties
can still be found growing freely in the ruins of ancient
Greece and Rome. During the Renaissance, snapdragons
were believed to bring charisma, glory, honor, and social
status; wearing them on one’s sleeve was believed to lead to
favorable receptions (Oyama and Baum 2004).
Today, snapdragons are cultivated throughout the world.
ey were brought to America when colonists began to
populate the United States. Snapdragons are easy to grow
and were given the title of “Flower of the Year” in 1994 by
the United States National Garden Bureau (https://www.
deseretnews.com/article/335410/FOR-FLOWERS-94-IS-
YEAR-OF-SNAPDRAGON.html). Snapdragons are still
popular due to their showy owers that make eye-catching
bedding and container plants (Figures 1 and 2). e owers
sit atop a long, green spike and have a wide range of petal
colors, making it an excellent cut ower. In 2015, fresh-cut
snapdragon sales reached $12.18 million in the US, making
it a top ten fresh-cut ower (USDA 2015). In 2014 and
2015, the ‘Chantilly’ series and ‘Madame Buttery’ series
snapdragons were respectively selected as the “Cut Flowers
of Year” by the Association of Specialty Cut Flower Growers
(ASCFG, www.ascfg.org). In addition to the value of their
Figure 1. Snapdragon orets in a variety of colors.
Credits: Juncheng Li, UF/IFAS
2
Planting and Propagation of Snapdragons in Florida
showy and fragrant blooms, snapdragon leaves and owers
are also used in the treatment of tumors, ulcers, inam-
mation, and hemorrhoids; in Russia, oil is extracted from
snapdragon seeds as substitutes for olive oil (Tolety and
Sane 2011).
Flowers of snapdragons used to be just white or purple, but
today they come in a wide range of dierent colors, includ-
ing white, yellow, red, pink, burgundy, bronze, and orange
(Figure 1). ere are four categories of snapdragons based
on their height: dwarf (4–9 inches), short (9–12 inches),
medium (12–24 inches), and tall (24–36 inches) (Creel and
Kessler 2007). Dwarf varieties are bushy and commonly
planted as border fronts, edgings, window boxes, or in
mixed containers (Figures 2 and 3). Short plants are great
for edging or in small beds or baskets. Medium plants are
oen the most popular group and can be used as border
plants or as cut owers. Tall varieties with a dominant,
single-ower shoots are used as bold displays or cut owers
for fresh bouquets.
Snapdragon Cultivation
Planting Time
Snapdragons are cool season herbaceous perennials
but grown as annuals, especially in subtropical regions.
Although snapdragons can be grown across the whole
country, their optimum growth temperature ranges from
65 to 75°F (18 to 24°C), which limits their production in
Florida (Figure 4). In Florida, the ideal time for growing
snapdragons begins in late fall through early spring. High
temperatures in late spring, summer, and early fall greatly
stunt their growth and result in plants with limited or no
blooming.
Propagation
Seed Germination
Snapdragon production starts from seeds. Seeds are very
small with approximately 6,000 to 9,000 seeds per gram
(Figure 5A), and can be grown in 3–4 inch pots using rich,
well-drained soil with a pH between 5.5 and 5.8. A higher
pH can cause iron deciency in snapdragons. Snapdragons
are sensitive to high ‘salt’ levels in the growing medium,
and especially to ammonium (Creel and Kessler 2007). e
electro-conductivity should be less than 0.75 mS/cm, and
ammonium levels less than 5 ppm (Creel and Kessler 2007).
Figure 2. Snapdragons are commonly used in landscapes and as
container plants.
Credits: Creech and Alfred Huo, UF/IFAS
Figure 3. Snapdragon blooms.
Credits: Caroline Roper and Alfred Huo, UF/IFAS
Figure 4. Production map of snapdragons in the US and Canada.
Credits: USDA NRCS
3
Planting and Propagation of Snapdragons in Florida
For seedling transplanting, surface sowing seeds in 384-cell
trays is recommended.
If seeds are sown singly into cells, seeds can be suspended
in 0.01% agar using a disposal transfer pipette to dispense
a single seed into each cell. In this case, a plant preservative
mixture (PPM) with a nal concentration of 0.2% is recom-
mended to minimize the fungal development (Hudson,
Critchley, and Erasmus 2008a). For sowing seeds on a large
scale, a waxy weigh paper can be used for spreading several
seeds into individual pots; but seedling thinning will be
required aer germination. Seeds in pots can be exposed to
air without soil cover, but soil should be kept moist during
seed germination. To prevent the soil from drying out, pots
can be placed in a tray with a plastic cover. Seed germina-
tion can be improved by using one of two chilling treatment
methods: either by A) seed stratication, e.g. chilling the
seeds suspended in 0.01% agar or water in a refrigerator for
3–5 days before sowing; or B) chilling pots with seeds in a
cool room 40–47ºF (4–8ºC) for 3–5 days. Seed germination
will be more uniform aer a chilling treatment. Germina-
tion should occur in 7–10 days at 64–68ºF (17–20ºC)
(Hudson et al. 2008a).
Vegetative Propagation through Cutting
Snapdragons can be propagated through cuttings. To
propagate, rst nd a leaf node in the middle of a healthy
stem and cut it 20–50 mm immediately below the leaf
node (Hudson, Critchley, and Erasmus 2008b). Remove
the leaves from the bottom two-thirds of the shoot. Dip
the cut end in a solution containing 1% Indole-3 butyric
acid, 0.5% 1-naphthaleneacetic acid, or in any commercial
compounds like TakeRoot or FastRoot. Next, insert cuttings
into rooting substrate or soil (Hudson et al. 2008b), and
maintain them at high humidity (100%) or mist every 30
minutes in an enclosed container or chamber at 62–68°F
(17–20°C). Aer approximately 2–3 weeks, rooted cuttings
can be transplanted (Hudson et al. 2008b).
Plant Care
Seedling Care and Plant Transplanting
Aer radicles emerge, keep plants under high light (1,000 to
2,000 foot-candles). Maintain soil temperature at 65–75°F
(18–21°C) and keep soil evenly moist but not saturated for
rooting. Once the true leaves have developed in approxi-
mately 15–20 days, increase light levels to 5,000 to 6,000
foot-candles, because low light causes elongated feeble
stems and reduces owering. Allow soil to become rela-
tively dry between each watering but avoid wilting. ese
ideal conditions will promote root growth and prevent
mold development (Creel and Kessler 2007). Incorporate a
layer of ne sand onto soil to strongly inhibit mold develop-
ment, reduce small ies and fungus gnats, and prevent
weed growth. A half strength all-purpose fertilizer such as
10-10-10 product (150 to 200 ppm nitrogen and potassium)
can be applied every other watering. If growing below 65°F
(18°C), avoid ammonium-based fertilizers (Hanks 2014).
Before transplanting, lower the temperature to 60–62°F
(16–17°C) to make stems sturdy. Seedlings can be trans-
planted when they have two or three fully expanded, true
leaves. Take the entire plug with a healthy seedling and
transplant promptly into well-watered soil in a large pot
or ground bed. Be sure to use care during transplanting to
avoid root damage. For a large amount of transplants, plug
trays can be held at 36–39ºF (2–4ºC) under uorescent
lights at 250 foot-candles for 14 hours per day (Creel and
Kessler 2007).
Spacing
Spacing between snapdragons depends on the variety being
planted. Since they produce more side branches, dwarf and
shorter snapdragons should be spaced 6–12 inches apart.
Single-stem tall varieties should be planted in a 4-inch
diameter area to produce strong stems with superior length
and bloom quality. Two layers of horizontal netting will be
needed to support the stems, keeping them straight. Place
the rst net 4 inches above the soil level and the second at
6–8 inches above the soil level. As stems grow, continue
raising the second net.
Production
Aer the seedlings have 3–5 true leaves (Figure 5B),
maintain plants at 65–75°F (18–24°C) during the day and
56–64°F (15–17°C) at night to increase apical meristem size
and encourage robust stem growth. Apply one full-strength,
all-purpose fertilizer every third watering. Most snapdrag-
ons are not sensitive to photoperiod, but supplemental
Figure 5. Dierent growth stages of snapdragons. (A) Snapdragon
seeds; (B) one-week-old snapdragon seedlings; (C) three-week-old
seedlings; (D) bolting of snapdragon; (E) blooming spike with 5–6
orets.
Credits: Matthew Creech and Juncheng Li, UF/IFAS
4
Planting and Propagation of Snapdragons in Florida
light to maintain long days (16 h light/8 h dark) can greatly
promote owering. In Florida, snapdragons can ower
during the winter but not in the summer, suggesting that
growth and owering is inuenced by high temperature
instead of photoperiod. For fresh cut ower varieties, hold
at 45–50°F (7–10°C) for 6 to 8 hours or overnight before
cutting to extend postharvest shelf life. As cut owers, most
snapdragon varieties tend to shatter shortly aer being
fertilized by bees; therefore, growing plants in greenhouses
may improve ower quality.
Harvesting
For fresh-cut ower varieties, cut stems when 5–7 orets
are open (Figure 5E). Premature harvesting leads to poor
color development and reduced ower size as owers con-
tinue to open. Remove lower foliage and immediately place
snapdragon stems in warm water at 70–75°F (21–25°C)
containing oral preservatives; overnight, keep water
temperatures at 45–50°F (7–10°C) for 6–8 hours. Treat
with Ethyl Bloc™ to avoid shattering of ethylene sensitive
varieties. Snapdragon stems can be stored at 40°F (4°C) for
3–4 days in water.
Seed Production
Most wild species of Antirrhinum are self-incompatible,
meaning plants cannot be pollinated with their own pollen.
e domesticated snapdragon is self-compatible and recep-
tive to all pollen from other wild species, making it easy
to breed through hybridization. Snapdragon seeds can be
easily produced through self-pollination with no additional
work since stamens are generally longer than stigmas. Eort
and attention should be given to produce hybrid seeds from
outcrossing. First, bright yellow pollen from newly dehisced
anthers can be collected by scraping them from the anthers
with forceps. Large amounts of pollen can be harvested by
squeezing the ower and slightly tapping on waxy weight
papers, which are recommended for use since the pollen is
sticky. Second, fold back the ower petals of the bud before
the recipient ower and use forceps to pull the laments
and remove anthers. Lastly, use a toothpick to transfer the
pollen to the stigma of the emasculated ower. Alternative-
ly, a tiny brush with pollen can pollinate multiple owers.
Aer pollination, owers should be covered by mesh bags
to prevent contamination with other pollen. e petals will
shed o if fertilization is successful. Seeds can be harvested
by shaking the pods 4–5 weeks aer pollination.
Commercial Varieties for Florida
Almost all commercial varieties are not marketed as heat-
tolerant, although many snapdragon varieties have been
reported to be adaptable to a wide range of temperatures
and can grow well in the Florida winter season (Gilman
1999). Among them, ‘Floral Showers Mix’ from Benary
Seeds, ‘Aromas’ series from Goldsmith Seeds, ‘Snapshot’
series from Ball Seed Co., and ‘Twinny Mix’ series from
HemGenetics perform well in Florida, especially under
warm temperatures. It should be noted, however, that some
of them still suer in the Florida summer heat and will not
bloom.
Future Breeding Goals in Florida
To date, no snapdragon variety has been claimed to be
heat-tolerant, which makes it more challenging for Florida
growers to produce snapdragons year-round. An important
breeding goal is to improve heat and drought tolerance of
snapdragons and produce varieties that are able to adapt
to Florida climate. Producing varieties that can resist
shattering due to pollination and ethylene production from
cuttings would be another improvement. For fresh-cut
varieties, extended post-harvest life would be long sought
by growers.
Common Pests and Diseases
1. Wilting and stem rot
• Wilting and stem rot are usually caused by Pythium,
Rhizoctonia, or Phytophthora; seedlings will be killed by a
severe infection.
• Solutions: steam or fumigate soils; spray plants with
thiophanatemethyl or iprodione to control Rhizoctonia;
drench soils with a solution of commercial fosetylalumi-
num fungicide (e.g., Aliette from Bayer CropScience).
2. Downy and powder mildews
• Mildews are apparent as gray or white powder on leaves.
Seedlings are stunted due to infection. Infected plants
may fail to produce owers, and severe infections can kill
plants.
• Solutions: reduce greenhouse humidity; remove dead
infected tissues; spray plants with suspended sulfur or
other proprietary fungicide.
3. Botrytis blight
• Pale brown dead tissues covered with gray fungi appear
on shoots, leaves, and owers.
• Solution: spray the shoots with suspended sulfur or other
proprietary fungicide.
5
Planting and Propagation of Snapdragons in Florida
4. Rust
• Small yellow swellings form on leaves or stems and burst
to release rust-colored spores.
• Solution: spray the shoots with suspended sulfur or other
proprietary fungicide.
5. Root-knot nematodes
• Above-ground symptoms include yellowing, wilting, and
stunting, which resemble nutrient deciencies or drought
stress. Root symptoms include short roots and distinctive
swelling.
• Solutions: crop rotation; pre-plant nematicide treatments.
6. Flower rips
• Infested shoots and ower buds show small lesions of
dead tissue, and pollen is missing from anthers, which
results in discoloration and premature dropping of
owers.
• Solutions: treat foliage or owers with insecticides as
soon as thrips are found. Weekly applications may be
needed until control is achieved. Apply predatory mite
Neoseiulus cucumeris for biological control.
References
Creel, R., and J.R. Kessler. 2007. “Greenhouse Production of
Bedding Plant Snapdragons.” Alabama A&M and Auburn
University, 1–3.
Gilman, E. F. 1999. Antirrhinum majus Snapdragon. FP044.
Gainesville: University of Florida Institute of Food and
Agricultural Sciences. http://edis.ifas.u.edu/fp044
Hanks, G. 2014. “Snapdragons (Antirrhinum majus) as a
cut ower crop grown in polythene tunnels.” National Cut
Flower Centre/HDC Information sheet 5.
Hudson, A., J. Critchley, and Y Erasmus. 2008a. “Cultivat-
ing antirrhinum.” CSH Protoc. doi:10.1101/pdb.prot5051
Hudson, A., J. Critchley, and Y Erasmus. 2008b. “Propagat-
ing antirrhinum.” CSH Protoc. doi:10.1101/pdb.prot5052
Oyama, R. K., and D. A. Baum. 2004. “Phylogenetic rela-
tionships of north American Antirrhinum (Veronicaceae).”
American Journal of Botany. 91(6), 918–925. doi: 10.3732/
ajb.91.6.918
Tolety, J., and A. Sane (2011). “Antirrhinum.” In Wild Crop
Relatives: Genomic and Breeding Resources, Plantation and
Ornamental Crops, C. Kole (Ed.) 1–14. Springer-Verlag
Berlin Heidelberg.
USDA. (2015). “Floriculture Crops.” United States Depart-
ment of Agriculture.
