Greetings from the world of Clivia. While we are known for our resilience and striking, long-lasting blooms, we are not immune to challenges. To thrive in your US homes and gardens, we require protection from a few key pests and diseases that find us as appealing as you do.
Our broad, fleshy leaves are a prime target for several sap-feeding insects. Mealybugs appear as tiny, white, cottony masses in the leaf axils and on the undersides of our leaves. They pierce our tissues and suck our sap, weakening us and excreting sticky honeydew. Scale insects are more cunning, appearing as small, brown, bump-like shells adhered firmly to our leaves and flower scapes. They are stationary but just as draining. Aphids may also cluster on our new, tender growth and flower buds. All these pests not only directly harm us but the honeydew they produce can lead to sooty mold, a black fungus that coats our leaves, further inhibiting our ability to photosynthesize and breathe.
A particularly grave threat comes from the Clivia Borer, the larval stage of a moth (Brithys crini pancratii). While not widespread across the entire US, it is a known issue in some warmer regions like Florida and can be introduced through imported plants. The larvae are the true villains; they burrow into the heart of our leaves, tunneling down into the crown and even into our thick, precious roots. This internal feeding can cause catastrophic damage, often discovered too late as our leaves turn yellow, collapse, and rot from the inside out. An infested plant can be lost rapidly if not identified and treated immediately.
Our roots are thick and fleshy, designed to store water, making us highly susceptible to rot if our soil remains soggy. The primary issue we face is root rot and crown rot, caused by fungi like Phytophthora and Pythium or bacteria. These pathogens thrive in waterlogged, poorly-draining potting mix. The first sign you may see is our leaves turning yellow, becoming soft and mushy at the base, and eventually collapsing. The rot attacks our vital crown, destroying the growing point from which all new leaves and flowers emerge. This is often a fatal condition if it progresses too far, as it destroys our very foundation.
Several fungal pathogens, such as Colletotrichum (anthracnose) and Gloeosporium, can cause leaf spots on our foliage. These often manifest as small, brown, or yellowish spots that may enlarge, sometimes developing dark margins or concentric rings. In severe cases, the spots can coalesce, causing large areas of our leaves to die back. While rarely fatal, a significant infection mars our beautiful, evergreen appearance and reduces the leaf surface area available for capturing sunlight, thereby weakening us over time. These fungi are often encouraged by overhead watering, which leaves moisture sitting on our leaves, and by poor air circulation.
We are also vulnerable to viruses, such as the Clivia Mosaic Virus. This is a systemic infection that becomes part of our very cellular structure. Symptoms include chlorotic (yellow) streaking, mottling, or stippling patterns on our leaves, stunted growth, and distorted flower development. There is no cure for a viral infection. It chronically weakens our system, making us more susceptible to other pests and diseases, and can be transmitted to other healthy Clivia plants through the use of contaminated tools or via sap-sucking insects like aphids acting as vectors.
