An introduction to agaves plus photos of popular varieties
About Agaves
Among the largest of succulents, agaves are unfazed by harsh sun, high heat and lack of rain. Their statuesque, fountainlike forms lend a sculptural element to any landscape, and contrast beautifully with fine-textured ornamentals. They also make good firebreak plants and security fences.
Growing Conditions
Being indigenous to the New World (the American Southwest, Mexico and Central America), larger agaves store enough moisture to get by on rainfall alone and will thrive in nutrient-poor soils.
Although agaves like water, their roots---like those of most succulents---will rot in waterlogged soil.
With the exception of a few soft-leaved and variegated varieties, agaves want sun---the more the better in all but desert climates. Most are hardy to the mid- to high-20s F, and some go a lot lower.
Sharp points at leaf tips and along leaf edges can make agaves treacherous. I snip about a quarter inch from leaves' needlelike tips with garden shears.
Scalloped patterns on an agave's leaves are "bud imprints" caused by spines and teeth pressing into the flesh of inner leaves before they unfurl.
Containers
Agaves smaller than basketballs make excellent potted plants. Small agaves---there are many---look best displayed one to a pot.
Pruning
When cutting a damaged leaf, keep in mind that a straight-across cut at its midsection may spoil an agave's symmetry. It's best to make two cuts that trim the leaf to a "V" that resembles the leaf's natural tip. Or cut it all the way to the trunk.
Propagation
Large agaves that pup (not all do) can be thugs. They'll grow and spread rapidly, especially when given good soil and regular irrigation.
One of the most widely grown is A. americana (century plant), because it offsets so prolifically (free plants!) and needs no care at all...until those pups start to get big and form an unruly, ever-expanding colony.
See the Resources section of this page for great alternatives to A. americana that don't spread quite as enthusiastically.
Life Cycle
All but a few agaves are monocarpic, meaning they bloom once and then die. This may take as many as 25 years, but it will happen.
As it completes its life cycle, a mature rosette that has graced a garden for years sends up an asparagus-like flower stalk (most, but not all, branch). This dwarfs the plant and saps its energy until it eventually collapses and dies.
Some of the larger flower stalks are so thick and strong that they need to be cut apart with a chainsaw to remove them.
Flowers along the stalk eventually turn into miniplants (bulbils) or seed capsules from which new agaves can grow.
Only the individual agave that flowers dies. In some cases---notably with those involving Agave americana---a litter of pups will carry on.
Morning from Edinburgh, Scotland , could you please give me any tips on over wintering Agave's in countries with cold / wet winters , I don't have a greenhouse , I lost 23 last winter , they were in a plastic greenhouse , all rotted .
A: Hi Mark — Oh, dear, how disappointed you must be. Basically, the secret to growing any plant anywhere is to replicate its native conditions as much as possible. Agaves are from arid regions with lots of sun and minimal rainfall. Can you grow them in Edinburgh? Sure. You can grow them in the Antarctic…if you want to badly enough and have enough space and money for a climate-controlled greenhouse. I saw agaves flourishing in Montreal…at the Montreal Botanic Garden, in an immense greenhouse. And, for that matter, at Kew. But in private collections? Best to stick with small ones that you can keep indoors and give much the same warm, dry conditions you like yourself. -- Debra Lee Baldwin
Big Blue's Life and Demise Agave americana is commonly called “century plant” because it seems to take forever to flower and die, but Big Blue’s lifespan was only 20 years...[continue reading]
If you think I've ID'd these or any plants incorrectly, I definitely want to know. Please leave a comment or email me. Enjoy exploring this marvelous genus! — Debra Lee Baldwin