Agave potatorum
| Light | Bright light to full sun; tolerates a little shade |
|---|---|
| Water | Moderately in growth, allowing the soil to dry fully between; keep dry in winter |
| Soil | Gritty, fast-draining mineral mix (see Soil and potting mix) |
| Temperature | Keep above freezing; USDA zones 9b–11 |
| Propagation | Seed and, on some clones, offsets or bulbils |
| Toxicity | Sap can irritate skin; considered mildly toxic if chewed |
Agave potatorum is a compact, solitary agave from the highlands of southern Mexico, prized as one of the most ornamental of the smaller species. Its broad, rounded grey-green to blue-green leaves are edged with ornate, wavy teeth and tipped with a dark terminal spine, giving each plant a symmetrical, artichoke-like rosette. Widely grown as the butterfly agave, it is the parent of a great many collector hybrids and variegated selections.
Description
Agave potatorum forms a low, compact rosette typically 30–60 cm across, usually staying solitary rather than clumping. The leaves are broad, short and spoon-shaped, grey-green to powdery blue, and their margins carry conspicuous undulating teeth that vary in colour from grey to reddish-brown. Each leaf ends in a stout, dark terminal spine. The overall effect is a neat, geometric rosette with an almost sculpted quality, which is much of the reason for its popularity.
Like all agaves it is monocarpic: after many years a mature plant sends up a tall branched flower spike, blooms, sets seed and then dies. The greenish-yellow flowers, often flushed with red in bud, are attractive to pollinators, and the spike may also produce small plantlets (bulbils) in some plants.
Distribution and habitat
The species is native to the semi-arid highlands of the southern Mexican states of Oaxaca and Puebla, where it grows on rocky slopes and in open scrub at moderate to high elevation. There it experiences bright sun, sharp drainage and a pronounced dry season, conditions worth remembering when growing it in a pot. Regionally the plant is well known as papalometl (butterfly agave) and, like several other agaves, has a history of use in traditional distilled spirits. Harvested intensively for tobalá mezcal — and slow to reach maturity — it has been heavily depleted in the wild and is assessed as Vulnerable on the IUCN Red List.
Cultivation
Agave potatorum is an easygoing and rewarding plant for anyone with a bright spot and a light hand with the watering can. Grow it in a very free-draining, mostly mineral mix in a pot only a little larger than the rosette, and give it as much light as you can — bright indirect light indoors, or full sun outdoors once acclimatised, which keeps the leaves compact and well coloured.
Water thoroughly in the warm growing season, then let the soil dry out completely before watering again; through winter keep the plant cool and nearly dry to prevent rot. It is not frost-hardy, so in cold climates grow it in a container that can be moved under cover before the first frost. See Watering and Repotting for general technique.
Propagation
Seed is the most reliable method for this largely solitary species, and it is also how most of the variation prized by growers arises; sow onto a warm, gritty surface and keep lightly moist until germination. See Propagation — seed. Some clones do produce offsets around the base or bulbils on the spent flower spike, and these can be removed and rooted — see Propagation — offsets. Because a plant dies after flowering, saving seed or plantlets is the way to keep a favourite going.
Cultivars
A. potatorum has been selected and hybridised extensively. Variegated forms such as the popular yellow-margined Kichiokan (Kissho Kan, "lucky crown") are widely grown, and the species features in many named intergeneric and interspecific crosses valued for compact size and bold leaf shape. Variegated and crested selections are slower and a little more tender, and are often grown a touch shadier than the plain green form.
Common problems
- Rot — overwatering or a slow-draining mix causes the base or core to soften and brown; the commonest cause of loss.
- Etiolation — too little light stretches and pales the rosette, losing its tight symmetry.
- Pests — agave mealybugs (white fluff deep in the leaf axils) and, less often, scale; the agave snout weevil can be fatal where it occurs. See Pests and diseases.
See also
- Agave — the genus overview
- Soil and potting mix · Watering · Repotting · Propagation — seed · Propagation — offsets