Using Herbs as Border Plants for Your In-Ground Garden
I’m often asked if it’s ok to mix herbs into flower beds. And the answer is ABSOLUTELY!!!
In fact, I recommend it.
Herbs are a fantastic choice for bordering in-ground gardens, blending beauty, functionality, and fragrance. In Central Indiana, where the growing season stretches from May to October, (and beyond with some careful planning) herbs can define garden edges, repel pests, and attract pollinators while providing fresh flavors for your kitchen. Here’s how to use herbs as border plants in your in-ground garden, with top picks and tips for success.
Why Choose Herbs as Border Plants?
Herbs excel as in-ground border plants because they:
Deter Pests: Strong-scented herbs like rosemary and oregano repel insects such as aphids, cabbage worms, and deer.
Attract Beneficial Insects: Flowering herbs like lavender and chives draw bees and butterflies, boosting pollination.
Define Garden Edges: Compact or spreading herbs create natural boundaries, enhancing garden structure.
Offer Culinary Benefits: Harvest herbs for cooking while keeping your garden tidy.
Add Visual Appeal: Herbs provide diverse textures and colors, from thyme’s low carpet to lavender’s purple spikes.
In-ground gardens in Central Indiana often have heavier, clay-based soils compared to raised beds, so proper soil preparation is key to help herbs thrive in this climate’s warm summers and cold winters.
Top Herbs for In-Ground Garden Borders
Here are five herbs that shine as border plants in Central Indiana’s in-ground gardens, with planting and care tips:
1. Chives (Allium schoenoprasum)
Why It Works: Chives form tidy, grass-like clumps with pink-purple flowers that attract pollinators and aphid hunters like ladybugs. Their oniony scent repels aphids and Japanese beetles.
Planting: Sow seeds or transplants in May, spacing 8-10 inches apart in full sun. Loosen soil to 12 inches deep and mix in compost to improve drainage.
Care: Water regularly, keeping soil moist but not waterlogged. Cut back after flowering for fresh growth. Hardy to Zone 3, chives return annually.
Bonus: Snip leaves for soups or salads; flowers are edible.
2. Thyme (Thymus vulgaris)
Why It Works: This low-growing perennial forms a dense, evergreen edge. Its aroma deters whiteflies and cabbage worms.
Planting: Use transplants in May, spacing 10-12 inches apart in full sun.
Care: Water sparingly once established; thyme tolerates drought. Trim to maintain shape. Hardy to Zone 5.
Bonus: I find I can harvest this plant year round and use fresh or dried thyme in roasts or stews throughout the winter holiday season.
3. Lavender (Lavandula angustifolia)
Why It Works: Lavender’s silvery leaves and purple blooms add elegance while repelling deer and moths. It attracts bees for pollination.
Planting: Choose hardy varieties like ‘Hidcote’ for Zone 6a. Plant transplants in late May, 15-18 inches apart, in full sun. Mix sand and compost into soil to mimic Mediterranean conditions.
Care: Ensure excellent drainage to prevent root rot. Prune after flowering to keep compact. Mulch lightly for winter protection.
Bonus: Harvest flowers for crafts or culinary use.
4. Oregano (Origanum vulgare)
Why It Works: Oregano’s spreading growth creates a lush border that deters ants and spider mites. Its flowers attract beneficial insects.
Planting: Sow seeds or transplants in May, 12-15 inches apart, in full sun or light shade. Loosen soil and add compost for fertility.
Care: Water moderately; oregano handles dry spells. Trim to control spread. Hardy to Zone 5.
Bonus: Fresh or dried oregano enhances Italian dishes.
5. Cilantro (Coriandrum sativum)
Why It Works: Cilantro’s feathery, green foliage forms a vibrant border. It attracts ladybugs, hoverflies and parasitic wasps, which prey on aphids, and supports pollinators when it flowers.
Planting: Sow seeds or transplants in early May, 6-8 inches apart, in full sun or partial shade. Soak seeds for 24 hours to aid germination. Loosen soil and mix in compost for fertility.
Care: Keep soil consistently moist to prevent bolting (flowering too soon). Succession plant every 2-3 weeks for continuous harvests. In the warmer season (June-August) plant seeds in the shade of taller plants to help prevent bolting. Cilantro is an annual, so replant yearly; it may self-seed in mild winters.
Bonus: Harvest leaves for salsas, curries, or garnishes. If it bolts, no worries, let it go to seed (coriander) which can also be used as a spice.
Designing Your Herb Border
To create an effective in-ground herb border:
Vary Textures and Heights: Combine low thyme with taller flowering plants for visual contrast. For example, plant thyme along a rock border of roses, or daisies.
Ensure Accessibility: Place frequently harvested herbs like chives or cilantro near paths for easy picking.
Pair with Crops: Use herbs as companions—plant lavender near brassicas to deter cabbage moths or chives beside carrots to repel carrot flies.
Define Boundaries: Use herbs to outline garden beds or pathways, creating a natural barrier that discourages weeds.
Tips for Success in Central Indiana
Soil Preparation: In-ground soils in Central Indiana are often clay-heavy. Dig 12-18 inches deep, break up the soil mixing in a a measured amount of organic starter fertilizer like Epsoma Biotone Starter and top it off with a handful of compost for extra fertility.
Sunlight: Most herbs need 6+ hours of sun. Choose a site free from shade cast by trees or buildings.
Watering: Water deeply but infrequently to encourage deep roots. Overwatering in clay soils can cause root rot, especially for thyme and lavender.
Winter Protection: For perennials (chives, thyme, oregano, lavender), apply a 2-3 inch layer of straw or bark mulch in late fall to shield roots from freezing temperatures.
What to Avoid
Poor Drainage: Herbs dislike “wet feet.” Avoid low-lying areas where water pools.
Overcrowding: Space herbs to allow air circulation, reducing fungal diseases common in humid Indiana summers.
Frost-Sensitive Herbs: Herbs like basil are better as annuals or central garden plants, as they won’t survive Zone 6a winters as borders.
Final Thoughts
Herbs as border plants in your in-ground garden offer a perfect blend of form and function. In Central Indiana, hardy herbs like chives, thyme, lavender, oregano, and cilantro thrive with proper soil prep, defining your garden with beauty and purpose. Plant them in May to enjoy a fragrant, pest-resistant border all season long. Get creative with your design and savor the rewards of a garden that’s both productive and picturesque.
