Ixora

full sun (6 or more hours of sun hitting the leaves per day. South-facing window, no obstructions. Under grow lights, keep them 4-8 inches away for 12-14 hours), 6-8 hours daily, for best blooming. Partial shade is tolerated but reduces flower production. Indoors, a south- or west-facing window with direct light is needed. Insufficient light is the most common reason for failure to bloom.

high humidity (60-80%. Group your plants together, set them on a pebble tray with water, or run a humidifier nearby) is essential -- below 50% relative humidity, leaf edges brown and flower buds may drop before opening. Use a pebble tray or humidifier indoors.

Well-draining, acidic soil (standard peat-based potting mix is naturally slightly acidic, pH 5.5-6.5, which is perfect), pH 5.5-6.5. Acidic conditions are non-negotiable; alkaline soil causes chlorosis (yellowing leaves) and poor flowering. Amend with sulfur or use azalea/camellia potting mix. A good basic mix is 60% loamy soil (equal parts potting soil, compost, and perlite), 20% cocopeat, and 10% sand.

Alkaline soil is the most common cause of yellowing leaves. Spider mites and aphids are the typical pest problems. Chlorosis from nutrient lockout in high-pH soils is common in Florida landscapes. Root rot in poorly draining or waterlogged soil.