Tobacco Hornworm on Tomatoes

📐 FIELD GUIDE ILLUSTRATION

Tomato hornworm (Manduca quinquemaculata) identification illustration with labeled anatomical features — PestControlBasics.com

Original illustration by PestControlBasics.com. Use the labeled features above to confirm your identification.

🔬

PestControlBasics Editorial Team

Reviewed by Derek Giordano · Updated 2026

🔍 Identification

40-50mm at maturity; bright green; C-shaped curved white lateral markings (vs. diagonal straight stripes on tomato hornworm); red/pink horn (vs. black on tomato hornworm). Found on tomatoes, tobacco, and related solanums.

🧬 Biology & Behavior

Adults are the Carolina sphinx moth — large, fast-flying moth active at dusk. Single or two generations per year. Larvae feed for 3-4 weeks before dropping to soil to pupate. Braconid wasps (Cotesia congregata) heavily parasitize tobacco hornworms — parasitized larvae covered in small white cocoons should be left in place.

⚠️ Damage & Health Risk

Rapid defoliation of tomato, tobacco, and eggplant; direct feeding on fruit. A large mature larva can strip several branches in 2 days.

🔧 DIY Treatment

Bt (Bacillus thuringiensis kurstaki) — most effective when caterpillars are small. Spinosad spray. Hand-pick when visible. Blacklight at night makes hornworms glow greenish. Leave any individual with braconid wasp egg cases attached.

👷 When to Call a Pro

Rarely warranted for individual gardens.

❓ FAQ

How is tobacco hornworm different from tomato hornworm?

C-shaped markings (tobacco) vs diagonal straight stripes (tomato); red horn (tobacco) vs black horn (tomato). Both are green, both reach 4 inches, both attack tomatoes. Treatment is identical.

What is the white stuff on the hornworm?

Braconid wasp pupae — leave the hornworm alone. The wasps will kill it and then spread to parasitize more caterpillars in your garden.

Factor	Details
U.S. Range	All or most U.S. states
Regional Detail	Distribution varies — consult your local extension service for regional prevalence data.

Factor

Details

U.S. Range

All or most U.S. states

Regional Detail

Distribution varies — consult your local extension service for regional prevalence data.

📅 Treatment Timing Guide

Treating at the right time dramatically improves results. Pest control timed to the life cycle uses less product and achieves better long-term control.

Period	Action
Spring	Inspection and perimeter treatment before pest season starts.
Summer	Active monitoring and targeted treatments as needed.
Fall	Preventive treatment before overwintering pests seek entry.

Period

Action

Spring

Inspection and perimeter treatment before pest season starts.

Summer

Active monitoring and targeted treatments as needed.

Fall

Preventive treatment before overwintering pests seek entry.

💰 Professional Treatment Costs

Service Type	DIY Cost	Professional Cost
Initial inspection	Free (self-inspect)	$75–$150 (often credited to treatment)
One-time treatment	$30–$100 in materials	$150–$500
Annual service contract	N/A	$400–$900/year
Severe infestation	Often ineffective alone	$500–$2,500+

Service Type

DIY Cost

Professional Cost

Initial inspection

Free (self-inspect)

$75–$150 (often credited to treatment)

One-time treatment

$30–$100 in materials

$150–$500

Annual service contract

N/A

$400–$900/year

Severe infestation

Often ineffective alone

$500–$2,500+

Prices vary by region, property size, and infestation severity.

❓ Common Questions About 🐛 Tobacco Hornworm

How do I confirm I actually have this pest (not something similar)?

The most reliable confirmation is a physical specimen — capture one and compare to reference images on this page. For cryptic pests (bed bugs, termites), look for secondary signs: frass, shed skins, mud tubes, or bites with a specific pattern. When uncertain, a professional inspection is faster than months of misidentification.

Can I treat this myself or do I need a professional?

DIY is effective for small, accessible infestations caught early. Professionals are worth the cost when: the infestation is inside wall voids or structural elements, multiple rooms are affected, you have health-risk pests (hantavirus, venomous species), or DIY has already failed twice.

How long until the infestation is completely gone?

Expect 3–8 weeks for most infestations with proper treatment. Insects with dormant life stages (pupae, eggs) extend the timeline because those stages are impervious to most insecticides. Follow-up treatments at 2 and 4 weeks catch each new cohort as they emerge.

What's the most common mistake people make treating this pest?

Treating only the visible pest population while ignoring the harborage site, entry point, or breeding location. Killing adults provides temporary relief but the population rebuilds from hidden egg cases, pupae, or new arrivals through unaddressed entry points.

🐛 Tobacco Hornworm