Astrophytum capricorne - Goat's Horn Cactus
Goat's Horn is a nifty round cactus with white speckles and spines that feel like cats whiskers. In summer, it blooms fragrant yellow blossoms with red throats. This is a small cactus, perfect for a windowsill. Even in the garden it only grows a foot tall.
Astrophytum is native to Northern Mexico and likes milder conditions than most cactus. Perfect for zones 9-11, it prefers light shade to full sun, and is cold hardy to about 20 degrees F.
As the plant ages, more spines develop, but they're relatively sparse, pliable and fragile. Handle the plant gently so you don't knock them off. They look very cool.
Scarify the hard seed coat and soak seeds for a minimum of 24 hours in warm water, you should see the seed coats puff up, or swell. Surface sow, covering with a light layer of soil. Cover pot with plastic wrap and a rubber band to keep in heat and moisture. Place in a warm, sunny location, keep soil moist, but not soaking wet. Remove plastic wrap when you have seedlings.