Japanese Water Garden Plants

Japanese Iris

• Japanese irises (Iris ensata, cristata, japonica, laevigata, sanguinea and siberica) have flat, wide blossoms, rather than the vertical petals of the better-known bearded iris. The flowers are anywhere from blue to pink in color. The plants thrive in loamy, moist, water-rich but well-draining soil. Different species live in different USDA Hardiness Zones. For example, siberica requires Zone 2, while ensata prefers Zone 5. The Lewis Ginter Botanical Garden in Richmond, Virginia, recommends planting them in an area where you can view them from above; avoid planting them in areas where they may be exposed to lime.

Sawa Wasabi

• Wasabi is a common condiment alongside sushi, and you can grow the plant from which the spice derives within your water garden. Aquatic wasabi is called sawa wasabi, although both aquatic and dry-land wasabi have the same scientific name, Wasabia japonica. Wasabi will do fine in Zones 8 and above. It likes moist to watery soil, preferably in shallow, running water. If you do grow wasabi, however, note that grinding up the plant won't produce the exact flavor you may be used to. According to the journal Chemical and Engineering News, the paste you receive in a restaurant is more likely a mix of wasabi, mustard and other spices. Pure, freshly ground wasabi from the plant remains spicy for only a few minutes.

Lotus

• The lotus (Nelumbo nucifera) is a symbol of beauty, purity and rebirth. Yellow, orange and pink blooms rise up above the water's surface on stalks. According to Jgarden.org, the individual blooms don't last long, but the entire bed that you plant may produce flowers for up to six weeks. They are hardy to Zone 5, and you can plant them at any time of the year above Zone 7. The lotus requires full sun, and despite its underwater residence, don't plant them so that the rhizome is more than 1-1/2 feet below the water's surface. Note that some areas may consider the lotus invasive.

Sweet Flag

• Sweet flag (Acorus gramineus) looks like a puffy clump of grass. It is cold hardy to Zone 6. It works as a pond or stream border plant, either right at the edge or in the water. The plant and its surrounding soil must remain moist and not allowed to dry out at all. The plant produces small flowers that Floridata calls "insignificant." Floridata also notes that there is a second type of Acorus known for its scent; however, Acorus gramineus isn't as fragrant.