How To Breed Hornworms: The Complete Guide

Are you planning to breed your own hornworms to feed your pet lizard? Or perhaps you might want to become a commercial breeder? Here’s a guide on how to breed hornworms the right way.

Even though hornworms are pests that can destroy crops and vegetable gardens, they have many beneficial uses. For pet owners who have lizards like bearded dragons, geckos, or chameleons, these worms serve as a nutritious source of pet food. 

Having said that, you might be wondering if you can breed tomato or tobacco hornworms at home instead of buying them online to save money or even become a seller. Well, you can, and this article will show you how to do it.

Life stages of a hornworm

When hawk moths lay their eggs, it takes about three days for them to hatch. From then on, hornworms have a lifecycle of about four weeks, going from stage to stage. Here’s a breakup of the lifecycle of a hornworm by stages.

• Egg: Hornworm eggs are light green or yellowish green in color, with a pearly sheen. Hornworm moths usually lay their eggs on both surfaces of the leaves of nightshade plants.
• Larva: It takes about three days for the larvae to hatch out of the eggs. As they mature into an advanced larval stage, they can move around throughout the plant or even a different plant if needed.
• Pupa: When a hornworm is ready to pupate into moths, it drops into the soil below and burrows itself. A hornworm pupa is red, unlike green caterpillar pupae.
• Adult: The pupation stage ends with the emergence of adult moths. This is the final stage in the life cycle of a hornworm.

How To Raise Hornworms to Moths?

The female moths lay eggs from which a new generation of hornworms takes birth. You need to provide the right environment and food for them to grow at each stage. You should try to mimic the same conditions as they would in the wild, except for a few minor differences. Here is a primer on the right conditions you need to provide them as they grow.

How to keep the eggs?

Let’s start with the very first stage – the eggs. To make a hatching chamber, you can use a plastic cup (transparent, so that you can see inside) or something similar. An average cup is enough for 30 to 50 hornworm eggs.

Follow the steps below to create a hatching chamber:

• Put a food source in the container, preferably solid food like hornworm chow. If you use liquid food, wait for it to solidify. The layer of food shouldn’t be deeper than a quarter inch. 
• Next, put some plastic netting in the cup with one end of the netting extending into the food. The netting should be able to hold the food up when the cup is inverted.  
• Punch a few holes in the cup’s lid for airflow and place it with the inside facing up. Line the inside with two layers of paper towels, tissue paper, or filter paper. Place the eggs on the paper. 
• Now, invert the cup, place it on the lid, and gently shut the lid. Make sure to keep the lid on at all times. This way, the eggs will remain on the layer of paper.
• Keep the lid slightly raised from a solid surface to allow air supply.

When the eggs hatch, the larvae will start climbing up the netting to reach the food.

How To Keep The Larvae?

Don’t move the larvae right after the eggs hatch. Wait until they’re at least about an inch long. If you try to pick up worms smaller than that, you might accidentally squish them. Once the larvae are ready to be moved, follow these steps:

• Buy vials from a nursery to store your hornworm larvae. Place a single worm in each vial, along with some food. Alternatively, you may also use small deli containers or condiment cups.
• If keeping individual containers is too much work for you or you don’t have space for so many containers, you can use a large Tupperware box instead. Simply put the larvae at the bottom and put a gutter guard netting over them, with bottle caps underneath to keep the net raised.
• Now place hornworm food on the netting. This will allow you to clean out the frass or remove moldy food easily.
• If the lid isn’t transparent, you may cut out a section and glue a transparent plastic screen to it.
• For quick growth, it’s best to maintain a temperature of around 81° F near the container(s) using a light bulb. You may also delay the growth by providing a cool environment.

Once the hornworms are about an inch long, you can start setting some aside as feeders and leaving only a few to grow and become moths. 

Remember that each hummingbird moth can lay up to a thousand eggs in her lifetime, so you only need to set aside a few moths each time for breeding.

How To Keep The Pupae?

You’ll know your hornworms are ready to pupate once they’re around 3 inches long because they will stop eating. Their appearance will also change, and their color will switch to a lighter shade. In the wild, they would drop off from the leaves and start to burrow in the soil, so you need to provide them with a similar environment at this stage.

• Fill a container with a substrate like soil, moss, or eco earth. Next, simply shift the hornworms to this container. You might need multiple such containers for this stage.
• Once the hornworms are ready, they will burrow in the substrate. You might find them roaming around for a couple of days before they burrow.
• As the worms begin to pupate, their bodies will harden and change to a brown shade.
• The pupation stage will last two to four weeks. During this period, mist the container daily to ensure proper wing growth.
• You should also transfer the pupae to a different container with fresh soil every week. Else, the pupae might die and rot due to molding and the accumulation of feces.
• Try to place a lamp near the container to maintain a temperature of around 81° F and stimulate 14 hours of daylight.

How To Keep The Moths After Hatching?

As the pupation stage nears its end, you’ll need a flight cage to contain the moths. A simple screen cage should suffice for this. Here’s how to set up the cage:

• Line the floor of the cage with a plastic sheet so that any dirt kicked up by the moths won’t spill out through the bottom of the cage. Moreover, moths also secrete a liquid called meconium while emerging, which can be rather messy.
• These moths have a similar feeding style to hummingbirds (which is why they are often called hummingbird moths). They have a long proboscis, which they use to suck nectar from flowers and fruits. Hence, a hummingbird feeder would be ideal for feeding them inside the cage.
• These moths are picky eaters. The best way to provide them with the necessary nutrition is to feed them commercially available hummingbird food.

Ultimately, it’s time for the final stage – breeding. Place a tomato plant inside the cage for them to lay their eggs on. 

Hornworm moths lay a huge number of eggs, and it can get out of control if you don’t pick the eggs daily. Hornworm eggs are tiny in size and green in color.

Frequently Asked Questions

How To Find Hornworms?

The easiest way to procure hornworms for breeding is to buy them from a nursery, pet food store, or an online seller. 

These pests are a common pet food for lizards, so pet stores selling worms usually stock hornworms. You may also find them in nature, but don’t feed those to your pet as they might be toxic.

How long does it take for hornworms to reproduce?

Female moths can produce eggs startlingly quickly: in just three to four days after coming out from their pupae stage, they are ready to lay eggs. 

These eggs hatch in about three days, and then it takes the hornworms about three to four weeks to pupate into moths.

Do hornworms eat each other?

Hornworms are usually herbivores and rely on a fully plant-based diet. However, in one study, scientists found that caterpillars will resort to cannibalism if they spray a tomato plant with a substance that triggers it to produce toxic substances. So, it is possible. This is why it’s necessary to ensure they always have enough food available.

Do hornworms need water?

Although the hornworm’s body has a high moisture content, they don’t generally have to drink any. The moisture they absorb from the plant on which they are feeding is usually enough to keep them going. 

However, as they can’t feed while pupating, you need to keep the substrate moist by regularly spraying some water on it.  

Wrapping up

Now you know how to breed hornworms at home by helping them grow into moths and keeping the cycle going. 

If you have pet lizards, this should cut down your pet food costs as hornworms tend to be quite expensive. Thank you for reading, and let us know how you used this information for breeding your own hornworms!

Reader Emails

Over the years, our readers have sent us several emails on this topic. Please go through them below.

Letter 1 – Pink Spotted Hawkmoth Hornworm

Subject: Hornworm?
Location: Winston Salem
November 15, 2015 10:18 am
Found in a flower garden in November in piedmont North Carolina. About 3.5 inches long
Signature: btrus

Dear btrus,
We are confident that your Hornworm is that of a Pink Spotted Hawkmoth, a highly variable species, but your individual matches this image on BugGuide.  According to BugGuide:  “Larvae feed on Sweetpotato (Ipomoea batatas), jimsonweed (Datura spp.), pawpaw (Asimina spp.), and other plants in the Potato (Solanaceae) and Morning-glory (Convolvulaceae) families.”

Letter 2 – Spiny Hornworm from South Africa

Subject:  What type of caterpillar is it
Geographic location of the bug:  Ballito south Africa
Date: 01/04/2018
Time: 01:50 AM EDT
Your letter to the bugman:  Please could you let me know what type of caterpillar it is and are they poisonous it is about 10 cm long and as thick as a pork sausage
How you want your letter signed:  Very interested

Dear Very Interested,
When we first posted images of this Spiny Hornworm Caterpillar, Lophostethus dumolinii, back in 2011, it proved quite the challenge to identify.  We sought the assistance of Bill Oehlke with the identification.  At that time, we couldn’t locate any matching images online. We now found a matching image on Aylestone 8:  Biodiversity on my Farm and there is also an image on African Moths.  Hornworms, the caterpillars of Hawkmoths in the family Sphingidae, are not poisonous or venomous, and despite a sometimes fierce appearance, they are harmless to humans.

Letter 3 – Taro Hornworm from China

Chinese Spotted Caterpillar with one spine
Location:  Wuhan, (Hubei)China
August 18, 2010 11:07 pm
Found this walking back to my apt in Wuhan China! I almost stepped on him as he was crossing the street! Drawing the question why does the caterpillar cross the road?! I can’t seem to find any info that isn’t in Chinese! Any help would be appreciated in identifying the big guy =)!!
Erin Thompson

Hi Erin,
We got lucky because when we quickly read your letter, we thought the Sphinx Moth Caterpillar was photographed in Japan, so we searched the subfamily Macroglossinae on a Japanese Sphingidae website because this caterpillar reminded us of some of the Eumorpha caterpillars in North America.  After some searching, we believe this is a Taro Hornworm, Theretra oldenlandiae, セスジスズメ, or Yushuang tian-er, a highly variable caterpillar that is pictured on the Japanese Sphingidae website in many of its color morphs.  You may also find it on the Sphingidae of the Western Palaearctic website which indicates its range as China, Taiwan, South Korea, Japan and Russia and has this highly detailed description of the stages of the caterpillar:

“LARVA: Full-fed 60–80mm, width 11mm, horn 8mm. According to Bell & Scott (1937), in the first instar pale yellowish-green, with a short straight black horn. In the second instar, head yellowish-green, body dark green; eye-spots on segments 5 to 11 black above, yellow below; horn short, black with base yellow. By the third instar, head and body slate-colour. There is a dorso-lateral line of yellow spots on 3 and 4 on a background of deep black. Eye-spots with a round yellow pupil edged broadly with black, decreasing in size backwards. Horn black, a yellow spot on each side of its base. In the fourth instar, head slate-colour, body black. There is a slaty-black saddle-shaped shield on segment 2, with a pale yellow dorso-lateral spot on the front edge; spots on 3 and 4 as in Third instar; eye-spot on 5 and 6 with a round black spot in the middle of the yellow, on 7 to 11 of a darker shade of yellow. Horn long, thin, straight, black with a white tip and a yellow ring near the base.
In the fifth and final instar, head small, dull and smooth. Body dull and smooth, tapering fist gently then more sharply forwards from 8 and gently backwards from 8; segments 4 and 5 not much swollen. Horn straight, of medium length, thin, nearly cylindrical, tip truncate with a minute, low tubercle at each lateral angle; surface shiny, covered with very minute tubercles (Bell & Scott, 1937).
Head black; labrum canary-yellow; ligula black; basal segment of antenna canary-yellow, other segments whitish; mandible black. Body velvety-blackish on segments 2 to 4, rest of body plumbeous with short black stripes around the secondary rings. There is a dorso-lateral line of spots on 2 to 4, some yellow, some orange, continuing as a stripe formed of small grey dots, interrupted by the eye-spots, to base of horn. A broad, soiled, pale yellow subspiracular stripe is also present from 2 to 12, dotted with small black rings on 6 to 12. Eye-spots on 5 and 6 with a round black pupil in which lie two narrow, irregularly concentric rings of electric blue; this pupil edged narrowly above, more broadly elsewhere with orange, at the top and bottom of which is a crescent of electric blue; the whole edged broadly with velvety-black. On 7 to 11 the eye-spots are rather larger, pupil deep purple above shading to reddish-brown below, edged above and below with a crescent of electric blue, the whole edged broadly with velvety-black; a broad yellow band, crossed by black lines, lying along the front margin of segments 5 to 11, and passing over the dorsum from the dorso-lateral stripe. Horn black with the tip narrowly yellow or white; legs red; protege and claspers black. Spiracles elongate-oval, white with a broad fuscous band across the middle, and a narrow black rim (Bell & Scott, 1937).
The thin horn is movable in a vertical plane in all instars.  The larvae are mainly diurnal and prefer younger leaves, seedpods and flowerheads, often stripping growing shoots, particularly in the final instar. Several of the gaudy larvae can often be found on one small plant.“

Hi,
WOW you guys identified that very quickly! I was very surprised to see a response back when I rechecked my email! Thank you so much! I knew it had to be a moth!!
Thank you so much again for all the information; I will definitely be giving a donation for such a wonderful site!
Thanks
Erin

Letter 4 – Tersa Hornworms feeding on Virginia Buttonweed

Subject: Caterpillars!
Location: Benson, North Carolina
September 5, 2015 8:25 am
Dear Bugman,
I think I have an idea of what this caterpillar is but what I have a question about is what kind of plant its on and what the possibility is of other plants like it being around here. Your response will be very well appreciated.
Sincerely
Signature: Cory

Dear Cory,
You stated that you “have an idea of what this caterpillar is” though you did not provide that identification.  Your images show both green and brown color variations of the Tersa Sphinx Hornworms, and according to BugGuide, they feed upon:  “Madder Family, Rubiaceae, including Smooth buttonplant (Spermacoce glabra), starclusters (Pentas species), Borreria, Manettia; and Bignoniaceae: Catalpa. Also noted, in North Carolina, from Virginia Buttonweed, Diodia virginiana, also in the Rubiaceae.”  Though we are not “What’s That Plant?” we believe they are feeding on Virginia Buttonweed based on the images posted to Backyard Nature.