Last updated on August 25th, 2023 at 03:20 am
The whale’s tongue agave, also known as Agave ovatifolia, agave ovatifolia frosty blue, or just agave frosty blue, is an attractive, succulent plant native to the Sonoran Desert in Arizona and northern Mexico. It boasts slender, sword-like leaves with pale-green margins that measure up to 15 inches long by 4 inches wide and are often tipped with red or purple at the tips.
The leaves branch from the base of the agave, which can grow up to 6 feet tall; each leaf ranges from 5 to 25 inches long and 2 to 6 inches wide.
Agave ovatifolia has long, narrow leaves that resemble the baleen of the whale’s mouth. This plant typically grows to about four feet in height and spreads out from there to approximately seven feet, making it an ideal choice for landscaping purposes in zones nine through 11. This agave does best when planted in full sun and well-drained soil, where it can grow for decades with only minor maintenance provided during the occasional trimming session every couple of years or so.
Whale’s Tongue Agave (Agave ovatifolia) is the only species of agave native to the United States, and it’s native to the arid southern regions of Arizona, New Mexico, and Texas.
Despite its common name, Whale’s Tongue Agave isn’t actually related to whales or their tongues! It gets its name from its large, elongated leaves that grow in pairs (similar to whale flippers). The leaves are covered in tiny hairs that feel similar to the texture of a whale’s tongue and give this species its common name.
Origin and distribution
Whale’s tongue agave is native to Mexico and Guatemala. The plant is distributed throughout Texas and Louisiana, and in Mexico as far south as Chiapas. The frosty blue agave grows well in sandy or calcareous soils in open, full sun with ample air circulation.
Frosty blue also can be cultivated indoors, although growth tends to be slow. It thrives at temperatures between 50 and 70 degrees Fahrenheit. It does not tolerate temperatures below 40 degrees Fahrenheit for extended periods of time.
In most cases, outdoor plants are killed by temperatures below 25 degrees Fahrenheit for extended periods of time.
Frosty blue agave will grow into a large specimen if left alone; it has been known to reach heights of 20 feet or more with age. However, most gardeners prefer to keep frosty blue agave smaller than 6 feet tall by pruning regularly.
The plant can be propagated from cuttings, although success is not guaranteed. It also can be propagated from seed, which must be collected when ripe and sown immediately in the sterile growing medium. The seeds are very small and should be sown on top of the moist growing medium at a depth of about 1/16 inch.
Whale’s tongue agave propagation
Before you can plant your agave, it is essential to know how best to propagate it. There are many ways to do so; some are easier than others. You can share a leaf or a stalk with someone and simply wait for them to grow one for you, or you could just dig up an offset from your existing plant if that happens to be an option.
You may also choose to take cuttings of leaves or stems, but these tend not to root as easily as offsets. Whichever method you choose, make sure they’re clean and free of disease before planting them in the soil.
Cuttings should be about 2 inches long and placed about 1 inch deep into sandy soil with good drainage. For plants propagated from seeds, use cactus potting mix, available at most garden centers.
Once planted, water Whale’s tongue agave regularly and allow them to become established in their new home before transplanting outdoors. Be patient: it can take years for agaves to flower and reach maturity!
Whale’s tongue agave care information
Fast-growing Whale’s tongue agave thrives in full sun and is often used in xeriscaping. When it’s not blooming, it grows best in partly shady areas with regular water.
Frosty Blue’s thick, oval-shaped leaves have smooth edges and can grow up to 4 feet wide and 12 feet long, making them a great ground cover. The flowers are bright yellow, giving way to black fruit that looks like spiked pebbles.
Light requirement
Whale’s tongue agave needs a minimum of 4 hours of direct sunlight each day. Avoid placing it in the direct, hot sun in order to prevent leaf burn and even death. However, if you place it in too much shade or indirect light, or in partial shade during parts of the day, it won’t bloom or will have a significantly reduced number of flowers.
Soil/potting mix
Agave ovatifolia, or whale’s tongue agave, needs a soil mixture that drains well and stays evenly moist. Use equal parts compost and potting mix for best results. For really big plants you may need to add some perlite as well.
You should also make sure your plant is planted in a container with good drainage holes in it. If you don’t have any, drill some into your container before planting.
This is especially important if you live in an area where it rains frequently during the winter months because these holes will help prevent root rot from overwatering. Be sure to use containers with at least one drain hole on each side of the container so water can drain out easily no matter how heavy it rains.
Watering
Proper watering is crucial to growing Whale’s tongue agave. For mature plants, add a one-quarter inch of water each week in spring and summer. In fall and winter, decrease watering to every two weeks.
Overwatering will result in a loss of leaves and eventually death for an agave plant. Always allow your plants to drain thoroughly before applying more water. This can be accomplished by moving them away from standing water or pouring off the excess after each irrigation cycle.
Fertilizer
Whale’s tongue agave needs fertilizer twice a year. Add fertilizer to the soil in early spring and mid-summer, when agaves are dormant. Spread a 1- to 2-inch layer of fertilizer around each plant, but do not over-fertilize; too much fertilizer can burn agaves and even kill them.
A general-purpose 15-10-5 fertilizer will work well for whale’s tongue agave and other succulents. Be sure to follow instructions on how to apply fertilizer correctly, as different types require different applications.
For example, some liquid fertilizers should be applied directly onto plants and watered into the soil rather than spread on top of it. Be sure you know how your fertilizer should be used before applying it.
Temperature
Whale’s tongue agave is not a cold-hardy plant. It prefers temperatures between 50 and 70 degrees Fahrenheit but does well between 60 and 65 degrees. If temperatures exceed 75 degrees for more than a few days, it will die back to its root.
While short periods of higher heat are fine as long as they’re followed by cooler weather, above 85 degrees can kill it over time. The agave frosty blue doesn’t need much water.
Humidity
Whales-tongue agave thrives in high-humidity environments. When growing these plants, keep them away from drafts or windows and use a humidity tray, which consists of water sitting on top of a layer of pebbles that sit atop your potting medium. If you don’t have access to a humidity tray, simply placing your pot on a tray of wet pebbles will do just fine.
The ideal humidity range is 70 to 80 percent. You can measure your plant’s humidity with a hygrometer, which you can purchase at any home-improvement store. If your agave’s leaves are starting to curl or turn brown, it may be too dry; if they are wilting, it may be too wet.
Pruning
Frosty blue leaves are hard to miss on the whale’s tongue agave. These succulents like their air circulation and don’t require pruning to look great, but you may choose to trim their brown edges for aesthetics.
Trim as needed during spring or summer when temperatures are above 50°F. Use a sharp pair of scissors to cut off any brown tips from each leaf. Make sure your cuts are made at an angle rather than straight across so that water can still travel down from leaf tip to stem base.
When to repot
Whale’s tongue agave is a slow-growing, long-lived plant that can last for up to 30 years. They prefer potting soil rich in organic matter and should be repotted every two to three years during their spring or summer growing season. After repotting, it’s best to water them lightly until new growth appears.
They are drought tolerant but will grow better when given enough moisture. When watering your whale’s tongue agave, allow water to drain from its bottom holes before giving it more water.
This will prevent root rot. If you live in an area with freezing temperatures, keep your whale’s tongue indoors during the winter months and bring it back outside once temperatures warm up again. In addition to being frost-sensitive, they dislike cold drafts and are susceptible to spider mites if exposed to high humidity levels too often.
Dormancy/Winter rest
Like all plants, Whale’s tongue agave have dormancy periods. During winter months or during extended periods of cold temperatures, agaves go into a type of hibernation known as winter rest. During these times, it is important to keep them protected from frost and snow.
When properly cared for during dormancy, an agave can return from its winter rest in spring with minimal stress. Some gardeners choose to place their agaves in a cool, dry location such as a garage or basement where they will not be exposed to freezing temperatures.
Others choose instead to bring their plants indoors for safekeeping until warmer weather returns. If you choose to bring your plant inside, make sure that you do so gradually over several days by first bringing it outside during warm afternoons and then moving it back inside at night until eventually leaving it out only during daylight hours.
Whale’s tongue agave flower & fragrance
Whale’s tongue agave species is noted for its small, frosty blue flowers and its pleasant fragrance. In large populations, it can be very showy. Because of its fragrant nature, a common name for Agave ovatifolia is ‘sweet agave’.
The sweet fragrance from these plants makes them popular landscaping plants in warmer regions where they are cultivated as ornamentals.
Growth rate
Agave plants are fast-growing. In areas with a long growing season, such as U.S. Department of Agriculture plant hardiness zones 9b through 11, mature plants will top out at about 3 feet tall and 6 feet wide after five years but can grow up to 5 feet tall and 10 feet wide in a single year if left untended.
In areas with shorter seasons like USDA zones 5b through 8b, it can take 20 to 30 years for agave to reach maturity.
Toxicity
Whale’s tongue agave is toxic to animals. Symptoms of ingestion may include gastrointestinal upset, gastric irritation, vomiting, and diarrhea. Severe poisonings in humans have led to dehydration and even coma! Be sure to keep it away from curious pets and children.
USDA hardiness zones
Whale’s tongue agave thrives best in USDA hardiness zones 9 through 11. It can be grown as an annual outside of these areas, but it will not survive cold winters.
Pests and diseases
There are several pests and diseases that may afflict a whale’s tongue agave plant. If a fungal disease called powdery mildew attacks your plant, it will start by turning leaves brown and white in patches.
Powdery mildew is best prevented by keeping your agave well-watered and fertilized, but should you see signs of infection there are commercial fungicides available to treat powdery mildew.
Another common pest for agave plants is spider mites; these tiny bugs live on and around your plant, sucking out its juices with their needle-like mouthparts. Spider mites can be controlled with insecticidal soap or horticultural oil sprays; if severe infestations occur, however, it might be necessary to remove affected plants from your garden entirely.
Conclusion
Whale’s tongue agave (Agave ovatifolia) is a variety of agave that stays frosty blue all year long. It’s often used as an ornamental plant and has even been used in Mexican cooking to make tequila.
It can be grown in U.S. Department of Agriculture plant hardiness zones 9 through 11 and requires full sun exposure with well-draining soil for optimal growth.
