15+ Perfect Companion Plants for Knockout Roses

Knockout roses are a popular choice for many gardeners due to their vibrant blooms and hardy nature. Pairing them with the right companion plants can elevate your garden design and keep your roses thriving all season long.

1. Euphorbia for Unique Texture

Euphorbia adds unique texture to knockout roses.
Euphorbia adds unique texture to knockout roses.

The unique texture of euphorbia adds an unexpected element when paired with knockout roses. Its foliage creates a striking contrast, making it a favorite for adding depth and interest to garden designs.

Explore these options:

  • Euphorbia Seeds or Plants: Enhance your garden with euphorbia’s unique texture, complementing your knockout roses beautifully.
  • Quality Potting Soil: Ensure healthy growth for euphorbia with this rich, nutrient-filled potting soil.
  • Garden Pruning Shears: Keep your euphorbia and roses looking sharp with these reliable pruning shears.

2. Yarrow for a Splash of Color

Yarrow offers a vibrant splash of color with knockout roses.
Yarrow offers a vibrant splash of color with knockout roses.

With its umbrella-like blooms, yarrow adds a splash of color and texture to a garden with knockout roses. I’ve found it thrives in similar conditions, making it a reliable companion.

Possibly handy products:

  • Yarrow Plant Seeds: Grow vibrant yarrow easily, enhancing your garden’s aesthetic alongside knockout roses.
  • Organic Fertilizer for Flowers: Boost your yarrow and roses with nutrient-rich organic fertilizer for spectacular blooms.
  • Garden Mulch for Flowers: Retain soil moisture and suppress weeds using this effective garden mulch.

3. Russian Sage for a Wispy Backdrop

Russian sage offers a wispy backdrop to knockout roses.
Russian sage offers a wispy backdrop to knockout roses.

The airy, lavender-blue blooms of Russian sage provide a wispy backdrop that enhances the vibrant colors of knockout roses. Its drought tolerance makes it an ideal choice for low-water gardens.

You might give these a try:

  • Drought-Tolerant Garden Soil Mix: Enhance your garden’s health with this specially formulated soil mix for drought conditions.
  • Lavender-Blue Garden Fertilizer: Boost bloom colors with this premium fertilizer designed for lavender and blue flowering plants.
  • Ergonomic Hand Garden Tools Set: Make planting and maintaining easier with this ergonomic hand tools set for gardeners.

4. Verbena for a Long-Lasting Bloom

Verbena adds long-lasting blooms to knockout roses.
Verbena adds long-lasting blooms to knockout roses.

The vibrant clusters of verbena flowers bring long-lasting color to a garden of knockout roses. I’ve seen how their low-growing habit fills in gaps, creating a lush and colorful display.

Useful items to consider:

  • Organic Flower Fertilizer: Boost your verbena’s vibrant blooms with this nutrient-rich organic flower fertilizer.
  • Garden Hand Tool Set: Enhance your garden setup with this sturdy and versatile hand tool set.
  • Drip Irrigation Kit: Ensure consistent watering for your verbena and roses with an easy-to-install drip irrigation kit.

5. Hydrangeas for a Bold Color Contrast

Hydrangeas provide a vivid color contrast to knockout roses.
Hydrangeas provide a vivid color contrast to knockout roses.

Hydrangeas offer a striking color contrast with their bold blooms against the delicate petals of knockout roses. I love using this combination in shaded garden corners to create visual interest and depth.

A few things you might like:

  • Hydrangea Plant Fertilizer: Boost your hydrangeas’ growth and vibrant colors with this specially formulated plant fertilizer.
  • Garden Shovel: Make planting easier with a durable garden shovel, perfect for your hydrangea-rose setup.
  • Mulch for Shaded Gardens: Enhance soil moisture and reduce weeds, perfect for your hydrangea and rose corner.

6. Salvia for Height and Texture

Salvia adds height and texture to complement knockout roses.
Salvia adds height and texture to complement knockout roses.

The spiky blooms of salvia add height and texture next to the bushy knockout roses, making them a perfect pairing. I’ve seen how salvia’s vibrant purple hues can really make the roses’ colors pop in a mixed border.

Check if these fit your needs:

  • Artificial Purple Salvia Stems: Enhance your garden with artificial salvia that adds vibrant height and texture effortlessly.
  • Garden Pruning Shears: Keep your salvia and roses tidy with precise pruning for thriving, beautiful blooms.
  • Organic Fertilizer for Flowers: Nourish your salvia and roses with this organic fertilizer for vibrant, long-lasting blossoms.

7. Artemisia for Silvery Elegance

Artemisia adds silvery elegance to knockout roses.
Artemisia adds silvery elegance to knockout roses.

The silvery foliage of artemisia provides an elegant contrast to the vibrant blooms of knockout roses. I’ve used this combination to add a touch of sophistication to garden borders.

You might like:

  • Artemisia Plant Seeds: Enhance your garden’s elegance with easy-to-plant artemisia seeds for stunning contrast.
  • Garden Border Edging: Define your garden with elegant border edging, complementing the silvery artemisia and rose blooms.
  • Rose Fertilizer: Boost your knockout roses’ bloom with this optimized fertilizer for vibrant garden displays.

8. Sedum for Low Maintenance Beauty

Sedum provides low-maintenance ground cover with knockout roses.
Sedum provides low-maintenance ground cover with knockout roses.

Sedum is a fantastic low-maintenance plant that pairs well with knockout roses, offering year-round interest with its succulent leaves. In my clients’ gardens, sedum acts as a ground cover that keeps weeds at bay while enhancing the roses’ beauty.

Possibly helpful picks:

  • Sedum Ground Cover Seeds: Grow a lush, weed-controlling ground cover that complements your knockout roses effortlessly.
  • Succulent Garden Soil Mix: Enhance your sedum’s growth with this specially formulated soil mix for succulents.
  • Garden Border Edging: Define your garden space elegantly while keeping your sedum and roses neat.

9. Catmint for a Blue-Purple Hue

Catmint adds a cool blue-purple hue to the rose garden.
Catmint adds a cool blue-purple hue to the rose garden.

The soft blue-purple flowers of catmint create a lovely color palette with knockout roses and attract pollinators. I’ve found that its aromatic foliage also helps to keep pesky insects away from the roses.

Maybe worth checking out:

  • Catmint Seeds: Enhance your garden’s beauty and attract pollinators with these easy-to-grow catmint seeds.
  • Aromatic Herbal Tea Blend: Enjoy the soothing aroma and taste of catmint tea with this delightful herbal blend.
  • Organic Plant Fertilizer: Boost your catmint growth naturally with this nutrient-rich, organic plant fertilizer.

10. Coreopsis for a Sunny Disposition

Coreopsis adds a sunny touch next to knockout roses.
Coreopsis adds a sunny touch next to knockout roses.

The cheerful yellow blooms of coreopsis bring a sunny disposition to any rose garden, complementing the vivid colors of knockout roses. I often recommend this duo to clients looking for a lively and welcoming garden space.

Some ideas to consider:

  • Coreopsis Seeds: Brighten your garden with coreopsis seeds and enjoy a lively sunny atmosphere all season.
  • Organic Plant Fertilizer: Boost the growth of your coreopsis and knockout roses using this powerful organic fertilizer.
  • Garden Hand Tools Set: Equip yourself with essential tools to maintain your beautiful flower garden effortlessly.

11. Clematis for Vertical Interest

Clematis adds vertical interest with knockout roses.
Clematis adds vertical interest with knockout roses.

Pairing clematis with climbing knockout roses creates vertical interest and a stunning display of intertwined blooms. This combo has been a favorite in creating focal points in garden trellises and fences.

A few relevant products:

  • Wooden Garden Trellis: Elevate your garden design with a sturdy trellis perfect for climbing clematis and roses.
  • Climbing Plant Support Clips: Keep your climbing roses and clematis secure with handy plant support clips for healthier growth.
  • Organic Rose Fertilizer: Boost your plants’ health with organic fertilizer, ideal for nourishing roses and clematis.

12. Spirea for Structure and Form

Spirea provides structure and form with knockout roses.
Spirea provides structure and form with knockout roses.

Spirea shrubs offer structure and form to garden designs, perfectly complementing knockout roses. In my garden designs, spirea’s delicate flowers add an extra layer of beauty.

Items that may come in handy:

  • Outdoor Plant Fertilizer: Enhance your spirea’s blooms and growth with this easy-to-use outdoor plant fertilizer.
  • Garden Hand Pruners: Keep your garden looking pristine with these durable and precise hand pruners.
  • Decorative Garden Edging: Define your garden paths beautifully with this decorative and functional garden edging.

13. Marigold for Pest Control and Color

Marigolds offer color and natural pest control with knockout roses.
Marigolds offer color and natural pest control with knockout roses.

Marigold flowers not only bring a burst of sunny color but also serve as natural pest repellents for knockout roses. I often plant them at the base of roses to keep the garden vibrant and healthy.

Consider these options:

  • Marigold Flower Seeds: Plant marigold seeds near roses for vibrant blooms and natural pest control in your garden.
  • Organic Pest Control Spray: Use this organic spray to protect your knockout roses and marigolds from pesky garden pests.
  • Garden Planting Kit: Get this kit to simplify planting marigolds and roses, ensuring a healthy, blooming garden.

14. Boxwood for Evergreen Elegance

Boxwood adds evergreen elegance to knockout roses.
Boxwood adds evergreen elegance to knockout roses.

Boxwood provides year-round greenery and a classic backdrop for the ever-changing blooms of knockout roses. I’ve used it in formal gardens to enhance the timeless beauty of roses.

These products might be useful:

  • Boxwood Shrubs for Landscaping: Enhance your garden’s beauty with lush boxwood shrubs for a classic evergreen appeal.
  • Garden Hedge Trimmer: Keep your boxwoods perfectly shaped with a reliable hedge trimmer for neat garden aesthetics.
  • Organic Fertilizer for Boxwoods: Nourish your boxwoods and roses with premium organic fertilizer for vibrant, healthy growth.

15. Lantana for a Splash of Tropical Color

Lantana adds tropical color with knockout roses.
Lantana adds tropical color with knockout roses.

Lantana adds a splash of tropical color with its vibrant blooms, creating a lively garden when paired with knockout roses. In warmer climates, this duo thrives and attracts a plethora of pollinators.

A few suggestions:

  • Tropical Lantana Seeds: Plant these easy-care lanthana seeds for vibrant, colorful blooms that attract pollinators to your garden.
  • Pollinator-Friendly Plant Fertilizer: Boost the growth of your lantanas and roses with this pollinator-friendly fertilizer for vibrant blooms.
  • Garden Hand Tools Set: Equip yourself with essential tools for planting and maintaining your garden with ease and efficiency.

Text: Joyce Peterson