Can Crested Geckos Eat Hornworms? Safety, Prep & Frequency
Safe — OccasionallyFeeding frequency: monthly
Hornworms are a safe, hydrating live feeder for crested geckos but their poor calcium-to-phosphorus ratio and very high moisture content make them a once- or twice-monthly treat, not a staple. Always dust with calcium powder and choose worms no wider than the space between the gecko's eyes.
How to Prepare
- Source only captive-bred hornworms from a reputable feeder supplier — never use wild-caught specimens or any worm that may have fed on tobacco or tomato plants, as these contain alkaloids toxic to reptiles.
- Select worms no wider than the space between the gecko's eyes; discard or hold back any that have grown too large since delivery.
- Gut-load worms for 24 hours on leafy greens (collard, dandelion, or squash) to boost micronutrient content before offering.
- Dust the worm lightly with a phosphorus-free calcium powder (with D3 if the gecko lacks UVB) immediately before placing it in the enclosure — calcium will rub off quickly, so timing matters.
- Offer in a smooth-sided feeding dish to prevent escape into substrate, and remove any uneaten worms within 30 minutes to avoid stress from a crawling feeder.
Warnings
- Never feed wild-caught hornworms — tobacco plant exposure makes them toxic.
- Overfeeding causes watery stools and calcium deficiency; limit to 1–2 worms per session, 1–2 times per month maximum.
- Hornworms grow very fast — re-check size every 2–3 days after delivery and discard oversized worms.
- Do not offer as a staple; their 1:3 Ca:P ratio will contribute to metabolic bone disease over time without aggressive calcium supplementation.
- Juveniles under 12 weeks should receive feeders sized to roughly 1 cm or smaller — hornworms may be too large for very young geckos.
Nutrition Facts
| Moisture | ~85% |
| Protein (wet weight) | ~9 g/100 g |
| Fat (wet weight) | ~3 g/100 g |
| Calcium:Phosphorus | ~1:3 (unfavorable) |
| Feeder risk level | Low — if captive-bred and properly dusted |
FAQ
- How often can I feed my crested gecko hornworms?
- Limit hornworms to 1–2 occasions per month, offering 1–2 worms per session. Their high moisture content and poor calcium-to-phosphorus ratio make them unsuitable as a frequent feeder — use crickets or dubia roaches as a more nutritionally balanced weekly staple instead.
- Do I need to dust hornworms with calcium before feeding?
- Yes — calcium dusting is mandatory, not optional. Hornworms have a calcium-to-phosphorus ratio of roughly 1:3, meaning unduplicated feedings will deplete calcium reserves over time and risk metabolic bone disease. Use a phosphorus-free calcium powder with vitamin D3 if the gecko has no UVB source.
- Can hornworms be too big for a crested gecko?
- Absolutely. Hornworms grow rapidly and can reach 10–13 cm at maturity — far too large for any crested gecko. Stick to worms shorter than 2.5 cm for adults and under 1.5 cm for juveniles, and re-measure every 2–3 days after delivery since they can double in size within a week.
- Are hornworms better or worse than waxworms for crested geckos?
- Both are treats rather than staples, but hornworms are lower in fat (3% vs. ~22% for waxworms), making them a marginally healthier indulgence. Waxworms are more palatable and can cause faster appetite spoiling. Neither should replace nutritionally balanced feeders or a commercial crested gecko diet (CGD).
- My crested gecko ate a hornworm and now has watery poop — is that normal?
- Likely yes. The ~85% moisture content of hornworms routinely causes looser, more watery droppings for 24–48 hours after feeding. If the stool normalizes and the gecko is active and eating, no intervention is needed. Persistent diarrhea beyond 48 hours or signs of lethargy warrant a veterinary check for parasites or infection.