Plant Highlight: Agave striata
With its spiky balls of needle-like leaves, Agave striata does not look like a typical agave and is sometimes mistaken for a yucca when not in flower. Plants may be single-headed, but usually they put out offshoots to form a clump. The individual heads are normally between 1½ feet and 3 feet across (½ to 1 meter). The leaves are green in shadier situations, but may be glaucous or tinged red, pink, or purple in strong sun.
Many agaves have a definite time of year for flowering, but our plants of A. striata at the Ruth Bancroft Garden have flowered at various seasons, and 3 are in flower this November. The unbranched, slender flower spike is up to 7 or 8 feet tall (to 2½ m.). The flowers are tubular and about 1¼ to 1½ inches long (30-40 mm). Flower color is variable, ranging from green to pale yellow to purple; our plants now in bloom have a vivid green color (note that an accompanying photo shows a plant with purplish flowers that bloomed earlier).
Agave striata is widespread in eastern Mexico, from Coahuila and Nuevo Leon in the north down through southern Tamaulipas and San Luis Potosi to Queretaro and Hidalgo in the south. It is very similar to A. stricta, which occurs farther south in Puebla and northwestern Oaxaca, and plants of these two species have often been distributed under the wrong name. However, the rosettes of A. stricta are tighter and generally smaller, and plants of this species are even more inclined to form dense clumps. Also, the leaves of A. stricta are always green, lacking the silvery-bluish color often seen in A. striata, and never taking on the red or purple hues that can color up the latter. The flowers of A. stricta are a little shorter, funnel-shaped rather than tubular, and of a purple to reddish-purple color.
Though almost invariably found in nature on limestone or in limestone-derived soils, Agave striata is not particular about soil type in cultivation, and thrives in most any garden soil if sufficient drainage is provided. It is quite hardy, enduring temperatures below 20° F (-7° C), and it makes a striking garden subject.