Black-Spined Agave

Black-spined agave is an evergreen succulent whose tight rosettes of narrow, powdery blue-gray leaves end in dark, sharp spines. It is a sculptural choice for sunny gravel gardens and containers, where its compact heads can develop into a wider offsetting clump. ## Form and placement The dark marginal teeth and prominent terminal spine stand out against the pale foliage. Plant it where the sharp tips will not catch passersby, and use a fast-draining mineral soil. It suits a warm, sunny site; the [Oregon State University Landscape Plants database](https://landscapeplants.oregonstate.edu/plants/agave-macroacantha) notes that light shade may help in hot low-desert settings. ## Size and flowering The [Royal Horticultural Society](https://www.rhs.org.uk/plants/182186/agave-macroacantha/details) describes an evergreen clump to about 60 cm tall and wide, with branched purple-tinged green flowers after at least 15 years. Oregon State reports mature clumps may spread much farther as offsets accumulate, while individual rosettes remain smaller. Leave room for that gradual expansion. A flowering rosette dies after blooming, but the clump may persist through its offsets. ## Maintenance Use a gritty cactus mix or sharply drained ground; water during active growth, then reduce watering in cool or wet weather. Avoid standing water around the crown. Remove offsets only if the clump exceeds its allotted space, handling the plant carefully because both leaf margins and terminal spines are sharp.