From our perspective as gladiolus plants, our tall, vibrant flower spikes are a testament to our health. However, we are constantly under siege from tiny invaders who see us as a perfect meal and breeding ground. When we are weakened by these pests, our ability to photosynthesize, grow, and produce those magnificent blooms you admire is severely compromised. Here is a detailed account of our most common adversaries and what we need from you to survive their attacks.
To us, aphids are like tiny, relentless vampires. They cluster on our tender new growth, the undersides of our leaves, and even our developing flower buds. Their needle-like mouthparts pierce our tissues to suck out the nutrient-rich sap, which is our lifeblood. This direct drain of resources causes our leaves to curl, pucker, and turn yellow. Even more alarmingly, aphids excrete a sticky substance called honeydew, which coats our leaves and creates a perfect environment for sooty mold to grow. This black, fungal layer further blocks sunlight, impairing our photosynthesis. Perhaps most devastating is their role as vectors, transmitting deadly viral diseases from one plant to another as they feed.
If aphids are vampires, thrips are microscopic vandals. They are especially fond of our flowers, but they attack our leaves as well. They rasp away at our surface cells with their asymmetrical mouthparts and then suck up the oozing contents. The damage is unmistakable: on our leaves, you will see a characteristic silvery-white streaking and stippling. On our flower buds, their feeding can cause such distortion that the buds fail to open. If the flowers do manage to bloom, they will appear streaked, discolored, and deformed, with petals that look scraped and bruised. Thrips often hide deep within the flower sheath, making them difficult to spot until the damage is already done.
While the pests above ground are troubling, the enemies below are perhaps the most insidious. Bulb mites infest our corms, which are our underground storage organs and the source of our energy for the next growing season. These mites typically enter through wounds or areas of rot. Once inside, they feed on our stored nutrients, causing our corms to become soft, rotten, and unable to support healthy growth. If an infested corm is planted, the resulting shoot will be stunted, discolored, and may never produce a flower spike. This attack on our very foundation is a direct threat to our future existence.
We rely on you for a multi-faceted defense strategy. First, please practice good sanitation. Remove and destroy any of our foliage that is heavily infested and clear away plant debris at the end of the season where pests can overwinter. Encourage our allies; ladybugs, lacewings, and predatory mites are natural enemies of aphids and thrips and will provide a first line of defense. A strong blast of water from a hose can effectively dislodge aphid colonies from our leaves. For more persistent infestations, we may need you to apply insecticidal soaps or horticultural oils, which suffocate the pests without leaving harmful residues. As a last resort for severe thrips or mite problems, targeted miticides or systemic insecticides may be necessary. Most importantly, always inspect our corms before planting and discard any that are soft or damaged to prevent the introduction of bulb mites into the soil.
