Kalanchoe With Small Yellow Flowers

Species

• The florist kalanchoe (Kalanchoe blossfeldiana) is native to Madagascar and grows about 15 inches tall and equally wide. A frost-sensitive perennial, it produces numerous, rounded clusters of tiny, four-lobed flowers from fall to spring when the days are short. While the wild species produces red flowers, horticulturists developed numerous cultivars that bloom in other colors, including a soft yellow. Another species with yellow flowers is K. grandiflora, a native of southern India. It grows 18 to 32 inches tall as an erect or floppy-stemmed perennial. Its 1/3-inch wide, bright-yellow flowers occur anytime from midwinter to midsummer.

Summer-Flowering Insight

• When grown as houseplants, both of these yellow-flowering kalanchoes may bloom into the long-day months of summer. Usually the number of flowers on the plants is markedly reduced compared to the shorter days of the year. Florist kalanchoe plants are available for purchase year-round. Production greenhouses manipulate the length of day and temperatures to coax plants into bloom in summer. Depending on light, soil, watering and temperature regimes in the home, both yellow-blooming kalanchoes may bloom erratically across the year. Direct sunlight, cooler temperatures and drier soils from fall to early spring help these plants bloom profusely this time of year.

Floral Structure

• These two yellow-flowering kalanchoes are exception in the genus Kalanchoe, formerly Bryophyllum. More plants in the genus bear red, orange or salmon flowers, or intermediate shades, rather than pure-yellow blossoms. Moreover, while all species bear flowers with four lobes, many more species produce pendent, bell-shaped flowers, often held on tall, candelabralike stems. Both yellow kalanchoes' flowers have a rounded, bulbous base where the ovary lies, and then the four pointed petal lobes flare outward from the base. The individual blossom looks like a tiny trumpet or urn in side profile.

Growing Considerations

• Although succulent plants, yellow-flowering kalanchoes respond favorably to an evenly moist but fast-draining soil when sunlight is abundant and temperatures warm. From late spring to early fall, keep the soil, either outdoors in the ground or as a houseplant, lightly but consistently moist to promote lots of leafy stem growth. From fall to spring, keep the soil drier and ensure plants bask in as much direct sunlight but cooler temperatures to induce flowering. Cut off old flower stalks once the yellow blossoms fade or drop off. This tidies the plant and may result in a second flush of flowers. Fertilize lightly only in late spring to midsummer; overly fertile soil creates leggy and weak growth.