Agave Americana [a-GAH-vee, a-mer-ih-KAH-na] belongs to the Agave genus of succulent plants.
It’s a species of flowering plants in the Asparagaceae (Agavaceae) family, native to Mexico, and the United States in New Mexico, Arizona, and Texas.
You may hear it called by its common name including:
- Century plant
- Sentry plant
- American aloe
People like to call it the century plant, as it’s known to live a hundred years.
Unfortunately, most century plants only live 10 to 30 years.
It eventually produces a stalk of flowers and then dies.
In the meantime, follow these plant care tips.
Century Plant Care
Size and Growth
This agave plant produces large leaves which grow in a rosette.
Typically has gray-green leaves or blue-green leaves but some varieties have white stripes or yellow leaves.
Mature plants may have leaves measuring up to 3′ feet.
They are thick, long, and slender with jagged teeth along the edges.
Due to the prickly edges and long leaves, the plant needs plenty of space.
After several years it may have a spread of two or three yards, making it difficult to keep as a houseplant.
Agave filifera is a smaller variety with many of the same features, providing a suitable alternative for keeping as a houseplant.
Flowering and Fragrance
Toward the end of its life, the plant produces a tall, branched flower stalk containing yellow flowers.
The stalk may reach 20′ – 30′ feet, towering over the rosette of leaves below.
This plant is monocarpic, meaning it only flowers once.
After the flowers die, the plant dies.
Luckily, it also tends to produce numerous offshoots before it dies, allowing for easy propagation.
Light and Temperature
The century plant grows outdoors in USDA hardiness zones 8 or higher.
In cooler areas, grow indoors at normal room temperature.
It cannot survive freezing temperatures during the winter.
Bring it indoors or keep it indoors year round.
When kept outdoors, place it in a light, sunny area. Indoors, set it near a bright windowsill, but avoid direct sunlight as it may scorch the leaves.
Watering and Feeding
Ensure the plant receives plenty of water throughout the spring and summer.
Although A. americana is very drought tolerant.
Feed it every other week between April and September.
Stop feeding the plant at least a month before overwintering.
Feeding it too much before winter weakens the plant.
During the winter, the century plant goes dormant and may not require water at all.
Check it occasionally.
If the leaves start to droop more than usual, give it a little water.
Leaves at the bottom of the stalk grow in a rosette to help funnel water to the base of the plant.
Soil and Transplanting
The American century plant has a weak root system.
It requires light, porous soil.
For best results, combine a mixture of sand, peat, and clay.
The plant doesn’t need transplanting unless it gets too big for its current pot.
If it outgrows its current pot, repot the plant at the end of winter, before taking it outdoors.
The century plant doesn’t need grooming, but the sharp spines and leaf tips pose a danger to children and pets.
If needed, trim the tips with a pair of scissors or even wire cutters.
How to Propagate Sentry Plant
Use side shoots or cuttings to propagate agave Americana.
Over the years, a mature century plant produces side shoots which grow near the mother plant.
The side shoots form the rosettes.
Trim these shoots from the mother plant any time of the year except for winter.
After removing the side shoots, allow them to dry for several days.
This keeps the sap from leaching into the soil, which increases the risk of bacterial growth.
Wait for the cut surface of the side shoot to dry and then plant in sandy peat.
Use individual pots for each side shoot and place outdoors in light shade.
Mist the young plants whenever in full sun keep them from drying out.
After four to five weeks, start watering the plant normally.
To propagate with cuttings, follow the same steps.
Take cuttings any time between April and September, but wait until the following April before repotting.
Other Interesting Agaves:
American Aloe Pests or Disease Problems?
Brown spots appearing on the leaves indicate the plant is receiving too much warmth, dampness, or darkness.
Move the plant to a brighter spot.
Agave Americans tend to attract spider mites and scale bugs.
Remove the insects with a sharp knife or wipe them away with a cotton swab dipped in rubbing alcohol.
To get rid of the spider mites, wash the leaves with diluted rubbing alcohol.
Wash the leaves at least three times per week until the mites disappear.
Besides these pests and disease problems, it’s also important to watch out for the sap.
The sap of the century plant contains poisonous compounds causing severe skin irritation or digestive issues.
Keep kids and pets away.
Suggested Uses For American Century
Agave American grows best outdoors during the spring and summer.
Grow in a large container on a porch or patio.
Overwinter the plant in a greenhouse or room with large windows.
Most people are interested in Agave americana ‘marginata’ for the sweetener called agave nectar or for its use in making tequila, mezcal, or Mexican pulque.
Grown in southern California as an ornamental.