Silkworms - 12 pack

The rule keepers use is that a feeder should be no wider than the space between the animal's eyes. Width, not length, is what decides whether a feeder is safe.

Silkworms are the awkward case here, because they do not hold a grade. They grow continuously and cannot be held at one size, so check them against the eye-width rule on the day you feed rather than assuming they are the same as last week.

Twelve suits one animal fed silkworms as a treat or a top-up over roughly a week. If you feed them regularly, or keep more than one animal, the 25 pack works out better.

Do not over-order and plan to save the rest. Unlike mealworms, silkworms cannot be paused – they keep growing and eating whatever you do.

Silkworms are widely sold as a calcium-rich feeder. The published figures do not support that. Compiled analyses of commercially raised invertebrates put silkworm larvae at roughly 1 part calcium to 13 parts phosphorus – calcium-poor, in the same territory as mealworms.

Insectivores need that ratio reversed, closer to 2:1 in favour of calcium. The genuine advantages of silkworms are the soft body, the moisture and the palatability, and those are reason enough to buy them. The calcium claim is not.

Dust with calcium immediately before offering and feed straight away. Powder clings well to a silkworm, better than it does to a smooth mealworm, so a light coating is enough.

Gut-loading is not really an option with this species. Silkworms eat mulberry leaves or mulberry chow and very little else, so you cannot load them on a calcium-rich food the way you would a cricket. Dusting does the work.

Use calcium with D3 where the animal has no UVB, and plain calcium where good UVB is provided.

Keep them at normal warm room temperature, roughly 22 to 28 degrees, in a ventilated container. Do not refrigerate them – this is the single most common way keepers lose a pack. Cold kills silkworms rather than slowing them down.

Feed mulberry leaves or mulberry chow, keep the container dry underneath and remove any mouldy food promptly. Mould, not hunger, is what usually takes out a small pack.

Suitable for leopard and crested geckos, bearded dragons, skinks, water dragons, chameleons, frogs and turtles, at a size matched to the animal.

Not suitable as a sole diet, and not a calcium supplement. Not suitable if you cannot use them within a week or so, since they will outgrow the size you bought.

Silkworms do not bite, do not jump and cannot climb out of a smooth container, so they are among the safest feeders to leave briefly with an animal. Still remove any uneaten worms at the end of the day rather than letting them be lost in substrate.

Wash hands after handling feeders and keep the container out of reach of children.

• Exo Terra Calcium + D3 Powder – needed here, despite the silkworm's reputation.
• Zoo Med Stainless Steel Feeding Tongs – the practical way to offer a soft feeder individually.
• Black Soldier Fly Larvae 100g – the feeder that genuinely is calcium-positive.

Live feeders are supplied for in-store collection or local delivery, with our live arrival guarantee.

Are silkworms actually high in calcium?

No. Published analyses of commercially raised feeder invertebrates put silkworm larvae near 1 part calcium to 13 parts phosphorus, which is calcium-poor. Dust them with calcium before feeding, the same as crickets and mealworms.

Can I keep silkworms in the fridge like mealworms?

No. Refrigeration kills silkworms rather than slowing them down. Keep them at roughly 22 to 28 degrees Celsius in a ventilated container.

What do silkworms eat?

Only mulberry leaves or commercial mulberry chow. They will not take vegetables or standard insect gut-load, which is why silkworms are dusted rather than gut-loaded.

Should I buy the 12 pack or the 25 pack?

The 12 pack suits a single animal or trying silkworms for the first time. The 25 pack suits multiple animals or regular feeding, and only makes sense if you can get through them before they outgrow the size you need.