It is critical to know the eventual size of your agave before installing it in the garden. + Show More
Agaves are mostly sun-worshipping plants in mild coastal climates, once they reach landscape size. They grow better and look better with lots of light, regardless of the climate. They do not typically thrive in the shade. Where desert heat is an issue, or in marginal climates, most agaves will do better with some overhead protection during the hottest days of summer.
Most small to medium size agaves make excellent container plants, offering the advantage of portability, and this may be the only option in areas with winter cold. Agaves tend to grow smaller and slower in pots. Seriously underpotting an agave (leaving it root-bound for years) may stunt or stall its growth. On the other hand, providing a little extra space in containers (within limits) can be quite helpful in getting patio or greenhouse plants up to landscape size.
Agaves in cultivation enjoy good drainage and regular water when the soil is going dry, but not much sooner. They are dry growing plants. Landscape agaves can survive months of drought once they are established, though they prefer occasional water. The reversible symptoms of water deprivation include inward-curled leaves and a slouching posture. Tip dieback can occur as these plants consume their lower leaves for the moisture reserves they contain, also as part of the natural process of senescence, sometimes exaggerated when a plant needs a bigger pot.
In addition to mealy bugs and other sucking insects, agaves can also be victims of two specialist pests. + Show More
The agaves which offset or make bulbils are usually very easy to reproduce that way. A few inches of root is sufficient for an offset to get a running start, but rootless offsets (like bulbils) can be readily rooted. The most common agaves in cultivation typically form big clumps over time. Other plants may only offset sparingly, or not at all, or only after they flower. This depends a lot on the species or variety, also to some degree on treatment in cultivation.
Agaves are also readily grown from seed collected after the fruit has matured and broken open. Young seedlings enjoy some protection but prefer strong light, especially once they have formed a recognizable rosette. Growing these plants from seed allows you to appreciate the variability many of them tend to exhibit in terms of spines, size, color, offsetting behavior, and other features.
Agave has at times included other genera including Manfreda and Polianthes, with several changes over the course of the last century. Manfreda as a genus has been split and lumped three times since the 1800s; these plants (which are generally small, with fleshy, brittle, deeply guttered leaves, sometimes with purple spots) are now considered Agave. Furcraeas may be indistinguishable from agaves at a distance when they are not in flower. They are typically more frost sensitive and produce bulbils; their flowers are bell-like. Agaves are also related to Yucca, Beaucarnea, Nolina, Dasylirion, Hesperoyucca, and Hesperaloe, which share a lot of the same territory in habitat. The agaves and their closest relatives make relatively large, perfect (bisexual) flowers, while the Nolinas and their relatives make smaller, unisexual, creamy white flowers (each plant is male or female).
Greg Starr, Agaves: Living sculptures for landscapes and containers (2012)
Mary & Gary Irish: Agaves, Yuccas, and related plants (2000)
Howard Scott Gentry: Agaves of Continental North America (1982)