Discovering scars on healthy succulents from a nighttime feast is frustrating. Succulents store water in their thick leaves, making them attractive to garden pests and wildlife seeking hydration and nutrients. Identifying the specific culprit is the first step toward protection, as different pests require different management strategies. This guide reviews the evidence left behind and provides targeted solutions to stop the damage.
Decoding the Damage Symptoms
The injury’s appearance is the primary clue for identifying the nighttime visitor. Examine the edges and surfaces of the leaves and the surrounding soil for signs of damage.
Clean, sharp cuts or missing chunks from fleshy leaves indicate a larger pest, such as a rabbit or rodent. These animals take large bites, sometimes consuming an entire small plant. If plants are pulled out of pots or substrate is scattered, this suggests a digging animal like a squirrel, raccoon, or rat.
Smaller, irregular holes, scrapes, or “windowing” on the leaf surface are typically caused by smaller insects or mollusks. Slugs and snails leave ragged edges and thin areas on leaves. The definitive sign of a mollusk is a dried, silvery slime trail visible on the soil or pot surface in the morning.
Look for signs of tunneling or disturbance beneath the soil line or clean cuts at the base of the stem. Clean cuts near the soil indicate cutworm activity, a caterpillar that severs the plant stem while feeding.
Identifying Common Insect and Mollusk Pests
Nocturnal pests like slugs and snails are attracted to the moisture and soft tissue of succulents. These mollusks are active in cool, damp conditions and leave a characteristic slime trail. Management involves simple physical barriers and traps.
A ring of diatomaceous earth (DE) sprinkled around the plant acts as a physical deterrent. This fine powder causes dehydration by scratching the pest’s exterior. Alternatively, a shallow container of beer sunk into the soil creates an effective trap, attracting and drowning the mollusks.
For potted plants, copper tape wrapped around the container rim creates a barrier. The tape provides a mild electrical reaction when it contacts the mollusk’s slime, preventing them from crossing.
Earwigs are common nocturnal feeders, leaving small, irregular holes on leaves and hiding in dark spaces during the day. Trap earwigs by placing a rolled-up, damp newspaper or hollow bamboo near the plants before nightfall. The pests crawl inside for shelter, allowing for easy morning disposal.
Cutworms, the larval stage of certain moths, sever young succulent stems at the soil line. If a plant is detached, the cutworm is often curled up just beneath the soil surface nearby. Hand removal at night with a flashlight is effective, or apply Bacillus thuringiensis (Bt), a biological control that paralyzes the caterpillars’ digestive system.
Addressing Mammal and Rodent Intruders
Larger animals, especially rodents, cause significant overnight damage, often seeking water stored in the leaves. Rats and mice are problematic, leaving gnawing marks and small droppings near the plants. Physical exclusion is the most reliable method for deterring these feeders.
For individual plants, place a wire mesh cage or hardware cloth barrier over the succulent, burying the edges slightly to prevent burrowing. Repellent sprays using peppermint oil or capsaicin (pepper) can be applied to the surrounding area, as rodents dislike strong odors. If the problem is severe, tamper-proof bait stations placed away from pets and children can be used.
Rabbits and squirrels also feed on succulents; rabbits eat low to the ground, while squirrels dig and uproot plants. Low fencing, at least two feet high and buried into the soil, prevents rabbit access. Squirrels are often deterred by motion-activated sprinklers.
Commercial bitter-tasting sprays can be applied directly to the plants, making the leaves unpalatable to these larger herbivores. Exclusion methods must be maintained diligently, as animals exploit gaps in the barrier.
Implementing Preventive Measures
Protecting succulents long-term involves modifying the environment to make it less appealing to pests. Adjusting the watering routine ensures the soil surface is dry before nightfall. Watering in the morning allows moisture to evaporate, which discourages slugs and snails that thrive in damp conditions.
Removing fallen leaves and garden debris eliminates hiding spots for earwigs, slugs, and rodent nesting materials. Cleanliness reduces the shelter and dark, moist areas these pests seek during the day.
Potting succulents in a fast-draining, gritty soil mix minimizes water retention, lessening the appeal to moisture-seeking pests. Elevating potted plants off the ground, such as on a sturdy table, makes them less accessible to ground-crawling mollusks and rodents. Strategic placement in well-lit areas also reduces nighttime activity, as many pests prefer darkness.