If you’ve planted bulbs and they aren’t growing or you see damage on whatever manages to grow above the ground, you might be wondering if the slugs in your garden are eating your plant bulbs. Well, it turns out that…
Slugs do not eat healthy plant bulbs below the ground. But slugs will eat plant bulbs that are rotting from too much water, and any tender shoots, roots, leaves, or flowers of plant bulbs.
Let’s take a look at the parts of plant bulbs that slugs eat and why, what happens to your bulbs if slugs get to them, and how to be sure it’s slugs eating your bulbs and not some other garden pest.
What parts of plant bulbs do slugs eat?
Let’s look a little more closely at the parts of plant bulbs that slugs might eat.
Plant bulbs
Although it’s not unheard of for slugs to take an exploratory bite from a healthy plant bulb or to eat rotten plant bulbs, slugs are more likely to enjoy eating the shoots, roots, leaves, and flowers of plants. Some bulbs, such as those of daffodils, are actually poisonous to slugs.
This is why it’s much more common for slugs to eat other parts of your flowering plants, not the actual bulbs.
Also, bulbs need to be planted quite deep in the ground – as deep as three times their height. This means that most plant bulbs are 3 to 6 inches below the surface of the soil.
Can slugs even get to bulbs that are so deep underground? The jury is out on this.
- Some sources say that 95% of slugs live underground, up to 6 feet deep.
- Others say that some slug species burrow underground to hibernate for the winter, but not in search of food during the warm months.
- And other sites and gardeners on forums claim that slugs live under rocks and in the shallow top soil, not deep in the ground (and certainly not deep enough to reach your bulbs).
Based on the above research, it seems to depend on the type of slugs in your garden, the weather and temperatures in your area, the humidity and moisture in the air, and how hungry the slugs are.
Slugs don’t really like the taste of plant bulbs, and prefer rotting bulbs to healthy bulbs. So there’s not much reason for them to spend the time and energy burrowing that deep to eat something they don’t like, even if they can get to them.
The verdict: Your bulbs are pretty safe from slugs but not from other animals, such as squirrels.
Here’s a video on how to plant and protect your bulbs for the best results:
Plant shoots
Slugs often eat the shoots of plant bulbs before they break through the ground. Many people think that slugs eat the bulbs, but the slugs are eating the sprouts coming out of the bulbs.
Because slugs eat the shoots before they break through the soil, gardeners never see these shoots, or they see weak and damaged shoots and flowers.
Plant leaves
Slugs love plant foliage, especially tender young leaves.
When they find a leaf they like, slugs make big holes in it, eat around the edges of the leaf, or strip long slivers out of it.
Whatever they do, slugs can cause quite a lot of damage to a bulb plant’s leaves.
Flowers
Plant bulb flowers are delicious to slugs, and they’ll often slide up to eat the buds and open flowers of your plant bulbs when they can, even if the actual bulb is poisonous to them.
Slugs are born to reach your flowers. A slug’s slime is a really thick mucus, and can be compared in strength to some adhesives. Slugs are sticky, which is why they can stick to and slide up stems to reach the very tops of fully grown plants, all to eat the flowers there.
What happens to your bulbs if slugs eat them?
Whether slugs are eating your plant bulbs’ stems, leaves, or flowers, slugs can cause severe damage. Once slugs start gnawing on your plants, at best, you’re left with ragged and ripped-up plants. At worst, the slugs do enough harm to cause permanent damage to the plants or kill them.
Here are some of the things to expect if slug damage is not managed or removed altogether:
The plants won’t catch enough sunlight
Leaves are a plant’s food factory. The leaves on a plant catch rays of sunshine from the sun, and the plant uses a process called photosynthesis to turn this sunlight into food.
But if the leaves of plants are too damaged and weak, they cannot catch any or enough sunlight for the plant to feed itself, and the plant may wilt over time and eventually die.
The plants won’t grow
Although slugs eat many parts of a plant, they prefer to eat the youngest and most tender bits. Because of this, slugs often start eating a plant as soon as it begins growing out from the bulb or seed.
If there are enough slugs eating the same plant, your plant might never reach the surface of the soil, or be eaten as soon as it does. You might think you have dud bulbs that won’t grow, but there’s nothing wrong with the bulbs – slugs are eating the shoots before you ever see them.
How to tell if slugs are eating your plant bulbs
Many animals and pests love eating plant bulb shoots, such as squirrels, deer, beetles, worms, you name it.
And because slugs primarily feed at night, you might never see them doing their damage while it’s happening.
One of the best ways to tell if you have slugs is to go out at night with a flashlight and check your plants. Look at the plants’ leaves, top and bottom, the stems, and the flowers. If you find a slug, there’s probably more because they follow each others’ mucus trails.
Slugs look like snails, but they don’t have a hard outer shell on their back. In fact, there are quite a few differences between slugs and snails that you might not even know about.
If you don’t want to spend an evening outside with a flashlight, look for the following common signs of slugs early in the morning:
- Slime trails on leaves, stems, or along the ground near your plants
- Large holes in flowers’ leaves and/or petals
- Numerous instances of bulbs or seeds not producing visible shoots and plants
- Damage to plants in early Spring, before other insects come out
- Half-moon/concave holes around the edges of leaves
- Holes in the buds of tall flowering plants
- Seedlings with missing leaves
If you find slugs eating your bulbs or plants, or you think you have slugs, click here to read my post on what stops slugs in their slimy tracks.
Final thoughts
Slugs are not likely to eat any healthy plant bulbs, but they will eat bulbs that are rotting from too much water. Slugs will also destroy your tender plants as the grow out of the bulbs.
If you suspect a slug problem, handle it immediately or it’ll only get worse.
