Yellow shrimp plant (Pachstachys lutea), sometimes called the lollipop plant or yellow candles, is a round-shaped tropical shrub that bears candle-like flower spikes of yellow bracts and tubular white flowers that attract hummingbirds. A moist, organic-rich soil with a partial sun exposure and frost-free growing conditions allow it to become a robust plant with many flowers from spring to autumn.
Native to tropical Central America, yellow shrimp plant will be killed by prolonged exposure to subfreezing temperatures. A light frost will kill above-ground foliage and stems, but regrowth sprouts from low stems near the ground. Gardeners regard it appropriate for year-round garden use in USDA Plant Hardiness Zones 10 to 15. Elsewhere it is used as a seasonal annual bedding plant for borders and containers.
In tropical regions, this shrub should receive partial sun to partial shade, no more than four to six hours of direct summer sunlight. Excessive light in the height of summer can cause leaf wilting and leaves becoming yellow-green. In cooler summer areas or where soil moisture is consistent, slightly more direct sunlight is tolerated. Indoors, provide as much direct light as possible to encourage flowering.
Grow yellow shrimp plant in a moist, well-draining soil that is not alkaline in pH. A sand or loam with organic matter incorporated is an ideal setting, and in containers use a quality peat-based potting mix. Avoid heavy clay or soggy soils as well.
Because the soil in which this plant grows is well-draining and is never soggy, regular watering from spring to autumn ensures a soil that is consistently moist. Periods of drought or dry sandy soil will inhibit growth and cause leaves to yellow or drop. In winter, soil moisture is kept slightly drier but never bone dry.
Yellow shrimp plant responds well to applications of liquid or granular all-purpose fertilizers in the warmth of the growing season. In spring, large unkempt plants may be pruned back severely to 6 to 12 inches in height and allowed to rejuvenate. Although the yellow flower bracts are long-lasting, they may be trimmed off to encourage side branches and flowers to grow later in the year.