Bulb aquarium plants

Set the bulb with any visible growing point up, and keep that point clear of the substrate. Depth varies by plant, from resting on top to half or more in the substrate for most crinums and many aponogetons. If it floats, let it float; it sinks once it sprouts. A bulb bought dry can take three or four weeks to wake in water above 72°F (22°C), and a bulb that turns soft or smells is dead. Bulb plants feed from the roots more than most aquarium plants, so a root tab under a lily or an aponogeton makes a visible difference. Medium light suits nearly all of them and CO2 is optional.

Several bulbs are among the fastest plants in the catalog. The red water lily and Aponogeton crispus, undulatus, ulvaceus and boivinianus all list fast growth. They can put out a leaf every few days when established and will shade a tank in a month. The tiger lotus and red tiger lotus stay compact only if you keep pinching off the leaves that head for the surface; leave them and the plant switches to floating pads and shades everything underneath. Trim leaves at the base of the stem, not halfway.

Aponogetons and some lilies grow hard for months and then die back to the bulb. That is dormancy, not death: leave the bulb in place, or lift it and store it cool and damp for a couple of months, and it usually returns. The crinums do not go dormant. The two lace plants, Madagascar lace and Henkel's lace plant, are the difficult bulbs in the list. Both want cool water, 64 to 75°F (18 to 24°C). The Madagascar lace may rest and shed leaves, and Henkel's lace plant needs no hard dormancy. Their perforated leaves collect algae in a bright tank. Aponogeton natans, crispus and undulatus are marked easy and are the steadier aponogetons if the lace plants put you off. Aponogeton capuronii is less prone to dormancy than most. Aponogeton boivinianus needs a dormant rest, when the bulb sheds its leaves.

The big aponogetons and the crinums reach 19.7 to 39.4 inches (50 to 100 cm) and need a tall tank. For a 10 to 20 gallon (38 to 76 liter) tank, the dwarf aquarium lily and micrantha lily stop at 9.8 inches (25 cm). The banana plant fits as well at 5.9 inches (15 cm). The orchid lily makes no floating leaves and stands 15.7 inches (40 cm) tall, too tall for these tanks. Every profile lists height; check it against the water depth you actually have.