As a chrysanthemum, my vibrant blooms and lush foliage are a point of pride, but they also attract a host of unwelcome visitors. These pests threaten my health and beauty, draining my energy and leaving me vulnerable to disease. From my perspective, here is a detailed account of the most common assailants and the treatments that allow me to thrive.
We often find colonies of tiny, soft-bodied insects—aphids—clustering on our tender new shoots and the undersides of our leaves. They pierce our tissues with their needle-like mouthparts to suck out our vital sap. This feeding weakens us, causing our leaves to curl, yellow, and distort. Worse still, they excrete a sticky substance called honeydew, which attracts sooty mold and can interfere with our photosynthesis. To treat an aphid infestation, a strong jet of water can dislodge them from our stems and leaves. For more persistent problems, insecticidal soaps or horticultural oils are effective, as they suffocate the pests without causing us significant harm.
Spider mites are minuscule arachnids that are difficult to see until their damage is advanced. They prefer hot, dry conditions and feed on our individual plant cells, piercing our leaves and draining their contents. The first sign is often a subtle stippling of tiny yellow dots on our foliage. As the infestation grows, fine, silky webbing becomes visible, and our leaves may turn entirely yellow, bronze, or brown and drop prematurely. Increasing humidity around us can deter them. Regularly spraying our leaves with water disrupts their activity. Miticides, insecticidal soaps, and neem oil are effective treatments, ensuring thorough coverage on the leaf undersides where they reside.
The tell-tale sign of leaf miners is the appearance of meandering, white trails or blotches across our leaves. These are the tunnels created by the larvae of small flies as they feed between the upper and lower surfaces of our leaf tissue. While a few mines are mostly a cosmetic issue, a severe infestation can reduce our photosynthetic capacity, weakening us overall. The most direct treatment is to simply remove and destroy the affected leaves, eliminating the larvae inside. For serious recurring problems, systemic insecticides can be used, which we absorb into our tissues, making them toxic to the mining larvae.
Thrips are slender, tiny insects that rasp and scrape at our flower buds and petals before they even open. Their feeding results in distorted, streaked, or scarred blooms that often appear bruised and fail to open properly. They can also feed on our leaves, causing silvery speckling. Because they hide deep within our buds, they are challenging to control. Consistent monitoring is key. Blue sticky traps can help monitor their presence. Insecticidal soaps and spinosad-based products can be effective if applied when the pests are active, targeting our buds and flowers.
These are microscopic, worm-like pests that represent a severe internal threat. They live within our soil and enter us through our roots or by splashing onto our lower leaves. They travel within our tissues, releasing toxins that cause devastating damage. Symptoms include wilting, stunted growth, and distinctive black or brown discoloration between the veins of our lower leaves, which eventually spreads upward. There is no cure once we are infected. The only course of action is to dig us up and destroy us completely to prevent the eelworms from spreading to other plants. The best strategy is prevention: always plant healthy, certified eelworm-free chrysanthemums and practice good crop rotation.
