Rue Herb: The Ultimate Guide to Ruta (Health, Garden & Safety)

Have you ever wondered whether the rue plant, also known as rue herb or Ruta graveolens, is really worth growing in your garden or using for health purposes? Maybe you’ve heard it called the “Herb of Grace,” or you’ve come across people using it as a natural insect repellent or even in traditional remedies.

But here’s the tricky part: some gardeners rave about rue for its strong pest-repelling powers and striking bluish-green leaves, while others warn about its toxicity and skin irritation. You might even find supplements or rue essential oil online, marketed with health claims, leaving you to wonder: Is this herb safe, or should I steer clear?

I’ve been gardening and working with herbs for years, and I know exactly how confusing it can be. That’s why in this guide, we’ll explore everything you need to know about rue, from how to grow it in your U.S. backyard or balcony, to its fascinating history, to the dos and don’ts of using it in herbal remedies. By the end, you’ll feel confident deciding whether rue deserves a spot in your garden.

What Is Rue (Ruta)?

Rue, or Ruta graveolens, is a perennial herb from the Rutaceae family. Native to Southern Europe and parts of North Africa, it’s now grown worldwide, including in the United States, mostly as an ornamental or medicinal plant.

The plant is easy to recognize: bluish-green leaves, a strong pungent smell, and small yellow flowers that bloom in summer. Rue thrives in poor, rocky soils, making it a resilient addition to herb gardens.

Historically, rue has carried many names and roles:

• Rue is native to the Mediterranean but has made its way across the globe. It thrives in poor, rocky soils and has been cultivated for centuries not just as a garden herb, but also as a sacred and medicinal plant.

• Known as the Herb of Grace, it was used in Catholic rituals to sprinkle holy water.

• In folklore, it was carried to ward off evil spirits, witches, or even the plague.

• In traditional medicine, it was used as an antispasmodic, anti-inflammatory, and even as a fertility aid.

But behind its cultural charm lies a complex chemistry that makes rue both valuable and potentially harmful.

Cultivating Rue – How to Grow Rue Plants

Growing rue is surprisingly simple once you understand its needs. Many gardeners in the U.S. grow rue for its low-maintenance nature and pest-repelling properties.

Soil and Climate

Rue doesn’t demand much. In fact, it almost prefers poor, rocky soil where other herbs struggle. The key is good drainage. If your soil tends to stay soggy, mix in sand or grit before planting.

• USDA Hardiness Zones: Rue grows best in zones 4–9.

• Climate: Hot and dry regions are perfect.

Sunlight and Watering

• Full sun is ideal, though partial shade works in very hot climates.

• Rue is drought-tolerant; overwatering can cause root rot.

Propagation

You can start Rue from seeds or cuttings. Seeds germinate best when sown in warm soil. Cuttings, however, are faster and more reliable.

Maintenance and Safety

• Prune lightly in spring to encourage bushier growth.

• Replace older plants after 5–6 years, as rue can get woody and less productive.

• Always wear gloves. Rue sap can cause phytophotodermatitis—a skin rash triggered by sunlight.

Pest Control

Rue itself is a natural pest deterrent. Many gardeners plant it to keep cats, dogs, and insects away. Interestingly, it also serves as a host plant for certain butterfly species, adding ecological value to your garden.

Rue Uses

The common rue herb has been valued for centuries for its versatility. Let’s break down its main applications.

Garden and Ecological Uses

1. Natural Pest Repellent

Rue is like a natural barrier against many garden pests. Gardeners have reported that it deters:

• Japanese beetles

• Aphids

• Flies

• Mosquitoes

• Even unwanted cats and dogs

It’s not a miracle cure, but planting rue alongside vegetables, roses, or fruit trees can reduce pest pressure.

2. Companion Planting

Rue pairs well with figs and roses, but avoid planting it next to basil or sage, as it can stunt their growth.

3. Attracting Butterflies

Here’s a fun twist: while most pests hate rue, certain swallowtail butterflies actually lay their eggs on it. If you love wildlife gardening, rue can help support pollinators and butterfly populations.

Culinary Uses

Rue has been used in Ethiopian coffee ceremonies and in traditional Italian cooking, where a leaf might flavor a meat dish or grappa.

But here’s the warning: rue is very bitter and potentially toxic in large amounts. If you experiment, use only one or two leaves to flavor a dish and always cook them—raw rue is harsher on the stomach.

I personally don’t recommend rue as a kitchen staple, but if you’re adventurous, it’s worth knowing about its culinary history.

Medicinal Uses

For centuries, rue was a go-to herbal remedy. Folk healers used it as an:

• Antispasmodic for muscle cramps

• Emmenagogue to stimulate menstruation

• Digestive aid for bloating and indigestion

• Anti-inflammatory for pain relief

Modern science has identified compounds like graveoline and rutin that show antioxidant and antimicrobial potential. But—and this is a big but—clinical evidence is still limited.

Rue can also be dangerous. Large doses can cause liver damage, miscarriages, or severe stomach upset. Herbalists today typically advise against internal use, except under strict professional supervision.

Active Compounds

Rue contains alkaloids like graveoline and flavonoids such as rutin, giving it potential antioxidant and antimicrobial properties. But these same compounds are responsible for its toxicity and photosensitivity risks.

Benefits & Scientific Evidence

Rue is often marketed as a medicinal herb, but what does science actually say?

• Anti-inflammatory effects: Studies suggest compounds in rue may reduce inflammation and pain.

• Antioxidant activity: Flavonoids like rutin can help combat oxidative stress.

• Antimicrobial potential: Some lab research shows rue extracts fight bacteria and fungi.

However, clinical evidence in humans is limited. Unlike popular herbs such as chamomile or peppermint, rue lacks strong modern trials to back its traditional claims.

In other words, while rue is promising in theory, it should be used carefully, and never as a replacement for proven treatments.

Safety, Risks & Side Effects

This is where things get serious. Rue may be natural, but it’s far from harmless.

Toxicity

• Pregnancy risks: Rue is an abortifacient and should never be consumed by pregnant women.

• Organ damage: High doses may harm the liver and kidneys.

Phototoxicity

Handling rue leaves and then exposing your skin to sunlight can cause severe burns, blisters, or rashes. This is due to its furocoumarin content.

Drug Interactions

Rue may interact with medications for blood pressure, anticoagulants, or sedatives.

Safe Practices

If you plan to use rue:

• Always wear gloves when handling the plant.

• Never consume large amounts or concentrated extracts without professional guidance.

• Use rue primarily as a garden herb or ornamental plant.

Conclusion

The rue plant, or Ruta graveolens, is a fascinating herb with a deep cultural history, striking appearance, and practical gardening benefits. It’s a powerful pest deterrent, a symbolic Herb of Grace, and a controversial medicinal plant.

But here’s the bottom line: rue should be grown with caution, handled with care, and consumed only in the smallest amounts if at all.

If you’re a gardener looking for a resilient, low-maintenance herb that doubles as a natural pest repellent, rue may be the perfect addition to your backyard or container garden. Just make sure you know what you’re dealing with.

Ready to explore more herbs for your garden? Check out my guides on Gardening tips.

Frequently Asked Questions (FAQs)

Is rue safe to ingest?
Only in very small culinary amounts. Medicinal doses carry serious risks like liver damage or miscarriage.

Can rue cause skin burns?
Yes, handling fresh rue in sunlight can trigger phytophotodermatitis, resulting in painful rashes.

Is rue really effective as a medicinal herb?
Traditional uses are well-documented, but modern scientific evidence is limited. Rue should not be relied on as a primary treatment.

Can rue grow in pots in the U.S.?
Yes. Rue grows well in containers, provided the soil drains well and the plant gets enough sunlight.

References 

1. TuaSaude. “Rue Plant.” Rue: 9 Health Benefits, How to Make Rue Tea & Side Effects