Scaevola plants fill a niche for gardeners seeking a heat tolerant plant for their summer containers: its thick stems ensure drought tolerance in full sun locations, even in triple digit temperatures. Scaevola plants are intriguing specimens for the hanging basket, where you can observe their hand-shaped delicate blooms up close. The plants will die at the first hint of frost, but it's easy to pot up a few cuttings for the next season.
Scaevola plants prefer to be on the dry side, but they are not true xeriscape plants and so do need occasional watering. Plants growing in wet soil may attract fungus gnats, or may experience root rot. Wait until the soil surface is dry to water. Wilted plants will perk up quickly after irrigation.
Choose a site with full to partial sun for best scaevola performance. Plants in hot, dry desert areas may remain more pert when placed in a location with dappled shade.
Accustomed to the lean growing conditions of its native Australia, scaevola plants require only a light feeding. Choose a balanced flower fertilizer low in phosphorus, which can cause flower and foliage discoloration. Apply the fertilizer once a month during the growing season.
Rich soil isn't necessary for thriving scaevola plants. While soil of average fertility is fine, good drainage is an important ingredient of healthy plant growth. When growing in the ground, amend heavy clay soils or use raised beds.
Like most trailing annuals, scaevola benefits from a little snipping here and there to keep it tidy and to encourage the plant to grow in a branching habit, rather than developing long, lanky stems. Scaevola is self-cleaning and does not need to be deadheaded, but you can cut it back by half after the first big flush of blooms to encourage new growth and spur even more flowering.
Scaevola plants grow vigorously in warm to hot weather. Temperatures below 60 degrees F will cause flowering to slow or stop. Temperatures between 70 and 85 degrees yield the happiest plants with compact growth, but hot temperatures are also well tolerated.