How to Grow Agave Indoors

Agave is a large genus of plants native to the arid and semi-tropical regions of Central and South America. There is a great deal of variety within the genus, with hundreds of named cultivars, most with a rosette shape and thick pointed leaves with spines along the edges. It can take several years or even decades for agave plants to mature, and they can live for many decades overall.

Agave plants are generally considered perennials, though many types are better described as multi-annuals that take several years to flower before dying—for the most part, agave plants only flower at the end of their lifespan. Their slow-growing nature and interesting appearance make the smaller varieties excellent choices as houseplants. Agaves do very well in dry indoor winter environments, though you must be able to give them plenty of sunlight.

The toxicity of agave plants varies widely by species. Some agaves have a long history of use as edible foods, but others, such as century plant (Agave americana) are notorious for causing caustic reactions when the sap contacts skin. Such species are generally labeled as having "minor toxicity" to humans, but they are not included on most lists of plants that are toxic to dogs, cats, and other animals.

Can You Grow Agave Inside?

Agave plants are very easy to grow indoors, provided you give them the warmth and sunlight they need. They need very little water and food, and overwatering or overfeeding can actually kill them. They also don’t need repotting very often because they are so slow-growing.  When growing agave as a houseplant, try to pick one of the species that lack spines. That will make your overall plant care, especially repotting, a lot easier.

Some popular agave species include:

• Agave americana: Sometimes called century plant, this species has beautiful bluish leaves with prominent saw-tooth spines. The pure species can become very large, so choose one of the cultivars that is smaller, such as 'Marginata', which will take a decade to achieve its full 6-foot stature.
• Agave victoriae-reginae: This small agave has upright leaves tipped with black spines; it measures only about 10 inches tall.
• Agave parviflora: This species grows less than a foot tall and wide and features white markings on its leaves.
• Agave colorata: This species grows about 1 to 3 feet tall and sports power-blue leaves.

How to Grow Agave Indoors

Sunlight

Agave plants thrive in full sun throughout the year. In very hot climates they might need a bit of shade because the harsh sun can burn their foliage. However, when grown indoors they should be set in your brightest location, ideally a south- or west-facing window. Rotate the container every week or two to ensure that all sides of the plant receive light and grow evenly. You also can move the container outdoors in warm weather, so your agave can luxuriate in full sunlight. This is not a plant that does very well under artificial lighting.

Temperature and Humidity

Agave species are desert plants, thriving in warm temperatures and low humidity. Indoors, make sure your temperature remains between 65 and 80 degrees Fahrenheit. And protect your plant from cold drafts, such as those from an air conditioner. Typically indoor humidity isn’t an issue for agave, as it won’t reach a high enough level that can cause rot and other problems for the plant. It can, however, be a problem if you move your plants outdoors for the humid summer months.

Watering

Established agave plants have a high tolerance for drought, but young plants will need a little more soil moisture. In general, water your plant every one to two weeks in the summer when it is actively growing, waiting for the top 2 inches of soil to dry out between waterings. For the rest of the year, water the plant about once a month, making sure not to let the soil completely dry out. 

Air Circulation

Good air circulation is essential in humid environments, where agaves can be susceptible to fungal diseases. This can be especially necessary during the humid summer months. If you are moving your agaves outdoors for the summer, give them plenty of space to ensure good air circulation.

Fertlizer

During the first couple of years, fertilize your container agave plant monthly in the spring with a balanced liquid fertilizer diluted to half strength. No fertilization is necessary for the fall and winter. Once mature, an agave plant generally does not need any feeding at all.

Pruning and Maintenance

Agave leaves need to be pruned off only when they die or become diseased. Remove leaves by cutting them off with sharp pruners near soil level.

Container and Size

When caring for agave as a houseplant, it’s important to pick a container that has ample drainage holes. Agaves have fairly shallow root systems, so shallow containers work well. Agaves are quite slow-growing, so give your plant a container that is only slightly bigger than the plant's spread. Ceramic or clay pots work well for agaves, though plastic pots can also work.

Potting Soil and Drainage

Agave can live in any soil type that has good drainage, though it prefers sandy or rocky soil with a slightly acidic to slightly alkaline pH. When planting agave in a container, use a quality cactus or succulent potting mix. To mimic the desert environment that agave plants favor, you can cover the potting mix with a thin layer of small pebbles.

Potting and Repotting Agave

Agave plants prefer not to be disturbed in their pots, and because they are so slow-growing, they generally need repotting only every few years. You’ll know it’s time when a lot of the roots are popping out of the soil and the plant has become too heavy for its container to anchor it. Select one container size up, making sure it’s sturdy but still fairly shallows. Carefully remove the agave from its old container, and replant it at the same depth in the new one, using fresh potting mix. Planting it too deep can rot the stem.

Moving Agave Outdoors for the Summer

Agaves will do very well if moved outdoors from late spring to early fall. In some regions, agaves are primarily outdoor patio plants, moved indoors only for relatively brief winter protection.

Considerations

Agaves that are not acclimated to bright sunlight may develop leaf burn if they are suddenly moved into bright outdoor sun. For the first weeks outdoors, give them increasingly long periods spent in full sun to acclimate.

If you live in a region with very high summer humidity and plentiful rain, agaves moved outdoors can sometimes be susceptible to fungal diseases. Here, it may be best to leave them indoors in a sunny but dehumidified environment.

When to Bring Agaves Back Inside

Agave plants should be brought back indoors at the first mild frost. A light frost doesn't harm them at all, but prolonged cold can kill an agave plant. In regions where your agave spends most of its time outdoors, the indoor environment should be relatively cool, allowing the plant to go into semi-dormancy.