Snails & Slugs

Copyright: Wikipests

Contents

1. Top Tips & Info
2. Symptoms
3. Susceptible Parts
4. Actions Needed
5. Ways to Prevent an Attack in the Future

Need the answer to a specific plant or pest query? Book a 1-to-1 video call with Joe Bagley, the website's friendly author, to overcome and address your niggling problem! Available on iMessage, WhatsApp, Facebook Messenger & more.

Top Tips & Info

• Eradication Difficulty - Easy
• Life Cycle: Snails 3 Years  &  Slugs 6 Years. 
• The female Snail can lay up to seventy eggs in her lifetime, whereas a female Slug can lay around thirty. Most eggs are deposited just below the soil line and resemble white circular balls. 
• Snails & Slugs can be brought onto a plant by two methods, either by being near an open window or during a short period outside during the spring or summer. 
• Small pests may go unnoticed for the first few weeks, but small circular bite marks will appear along the leaves in due course. 
• To eradicate an attack, take the plant outside and look around the entire foliage and pot. Check under its leaves, along the stems and around the pot. In some cases, the Snail or Slug will move onto other surfaces nearby to the plant's indoor location, so it's essential to be vigilant when addressing an attack.
• Unlike most houseplant pests, Snails & Slugs can be removed using just organic-based pesticides. Along with vigorously checking the plant, you can either spray the foliage with diluted Diatomaceous Earth (DE) or even ground-up used coffee beans. 

Symptoms

Small circular bite marks will develop along the foliage on the unfortunate plant. After a short period, the affected leaf will become yellow or brown and warrant it useless. Prune off the seriously affected foliage to improve the growing conditions. You may also see the iconic slime trails as the pest travels across the plant, and possibly onto nearby specimens. 

They are also known to eat the basal structures of tubers, small rhizomes and even corms. With your finger, move the soil that's next to the plant's base to see if it is under attack. If so, take the specimen outside and replace the top two inches with a fresh batch of the appropriate potting mix ('Houseplant' compost for tropical plants, 'Cactus & Succulent' compost for arid-dwellers, and so on). Keep an eye out for a potential relapse within the oncoming weeks by checking the plant's base for further damage. 

Typical damaged of a snail on a Peperomia.

 Slug damage sometimes looks similar to 'teeth marks' as seen on this Echeveria. 

Susceptible Plants & Parts

Most areas above the soil line will be susceptible to Snails & Slugs, including its basal structure like corms, tubers and rhizomes. Stemmed plants are more likely to house an attack on solely its foliage. 

Plants - All houseplants are tolerable to Snails & Slugs, including Elephant Ears, Monstera & Succulents. 

Actions Needed

1. Pick off any visible bugs with gloves, keeping them in a container as they may slowly escape. When returning them to the outdoors, never relocate them near tender plants (like Hostas) that are intolerable to dealing with a potential attack. This will only further cause damage to your ornamentals, whether they're indoors or out.

2. Take the plant outside, GENTLY washing the stem, leaves, and each cubbyhole using an outdoor hose. It's important to spray in at least three different angles to ensure thorough administration.

3. Once the plant is dry again, it's time to administer the Diatomaceous Earth (DE). This product is grounded diatom mantels (skeletons) that can be highly abrasive to many arthropods, including Mealybugs. Although the white powder-like substance may be soft to the human touch, the sharp tooth-like edges off each grain will begin to cut its way into the pests' eco-skeleton, causing significant discomfort and weakened health. After a period of several days, the infestation will decrease as the mature mothers won't be able sufficiently to lay her eggs.

N. B. - You will need to apply DE in two areas of the plant with different methods, too. You'll first mix a small sample of DE with water to create a diluted spray. Once this step is complete, you'll also sprinkle a thin layer onto the soil's surface to create a protective barrier against burrowing Slugs. 

3a. Dilution for its Foliage 

Mix the DE with water to create a more efficient solution to access the plant's cubbyholes and hard-to-reach areas. Add one tablespoon of DE to 500ml of water (0.11 imperial pints) and mix well. Finely mist both sides of the leaves and its stems so that the plant is covered in a thin film, which will begin its work within twenty-four hours once dry. We'd recommend waiting six weeks before deeming the specimen pest-free, as the critters could always reappear. If pests do return, follow the three steps mentioned above, along with the misting of its foliage with this solution. If the infestation is large, you may wish instead to opt for a chemical-based pesticide to destroy the infestation more effectively. DE is considered safe to both pets and humans and has no links to the development of illness or cancers.

3b. Sprinkling a thin Layer onto the Soil

Equally sprinkle a thin layer of DE across the soil's surface to create a protective barrier against the Snails or Slugs from burrowing or laying their eggs. You won't need much powder, so make sure that the layer is the depth of a piece of paper. After four weeks, you may remove the DE once it's felt that the pests have been removed. 

Ways to Prevent an Attack in the Future

At the local plant shop or garden centre, inspect the soil of any plants you wish to buy. Most attacks come from nearby windows or after being placed outdoors for a short while during the warmer months of the year. When placing your houseplant outdoors, it's crucial to regularly keep an eye on the specimen, whether its a tropical plant or arid-dweller. 

Finally, store your bags of compost well by keeping them tight and enclosed, out of dry or damp areas. Never use soil that has been left outside for any length of time, due to the very high risk of contamination.

Book a 1-to-1 Consultation with THE HOUSEPLANT DOCTOR™

Need realtime advice for your Snail or Slug situation? Book a video or message consultation with expert Joe Bagley, THE HOUSEPLANT DOCTOR™ (author or ukhouseplants.com). Choose between a ten or thirty-minute session & a platform of your choice (WhatsApp, FaceTime, Facebook Messenger or Zoom). Ask unlimited questions in one session, including queries on your dying/challenging plants, pests eradication, terrariums, repotting advice & everything in between! Available worldwide.