In the tropics & subtropics, drought-deciduous flowering trees are especially showy because they flower before the leaves emerge, i.e., they are protoanthous. Here’s Jacaranda mimosifolia. 📷: John CCBYSA2 #protoanthy #Bignoniaceae #Botany 🌾🧪🌱

Sassafras albidum is a spring-flowering tree that flowers before the tree’s leaves emerge; ergo, it’s protoanthous. Their tiny, yellow flowers are a welcome sight in the spring (for both winter-weary humans and pollinators). #protoanthy #Lauraceae #Botany 🌾🧪🌱

Another spectacularly ornamental tree is Cochlospermum vitifolium. This is the double-flowered cultivar. It makes these enormous flowers right before the leaves appear in the spring. It's protoanthous. #Bixaceae #protoanthy #Botany 🌾🧪🌱

The decoupling of leaves and flowers is common where there is a strong reason for dormancy: cold or drought. Forsythia is famous for flowering early in the spring, before the leaves emerge, sometimes even before the snow melts. #protoanthy #Oleaceae #Botany 🌾🧪🌱

Protoanthy (protoanthous/proteranthous) is when flowers appear before the leaves. Another Magnolia example: Many of the deciduous magnolias are protoanthous, like this hybrid Magnolia ‘Butterflies’. #Magnoliaceae #Botany 🌾🧪🌱
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This diagram shows how flower and leaf phenology and the difference between protoanthy and hysteranthy for both summer-dormant (upper two timelines) and winter-dormant (lower two timelines) plants.
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