Peonies are one of the most beautiful and long-lived perennials you can grow, producing large fragrant blooms every spring and early summer.

But if your peonies seem crowded, struggle to bloom, or never thrive the way you expected, nearby plants may be part of the problem.

Knowing what not to plant with peonies can help your flowers stay healthy, bloom better, and live for decades.

Peonies prefer sunshine, good airflow, and room to grow. Plants that crowd them, shade them, or compete heavily for water and nutrients can reduce flowering and create disease issues.

If you’re planning a peony bed, here are the plants best kept at a distance.

New to growing peonies? Read my guide on Best Time to Plant Peonies.

Need to move one? See Transplanting Peonies in Spring or Transplanting Peonies to Pots.

For healthy long-term growth, read How and When to Cut Back Peonies.

Why Plant Pairing Matters for Peonies

Peonies can stay in the same spot for many years, so choosing the right companions matters more than with short-lived annual flowers.

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Poor companion choices may cause:

Fewer blooms
Powdery mildew
Weak stems
Root competition
Slow growth
Constant transplanting later

Giving peonies the right neighbors helps them flourish.

Large Shrubs That Create Shade

Peonies need full sun for best flowering, ideally 6 or more hours daily.

Avoid planting peonies too close to:

Hydrangeas
Large roses
Overgrown boxwoods
Tall viburnum shrubs
Fast-growing hedges

As shrubs mature, they can shade peonies and reduce blooms.

Better Idea:

Plant peonies in front of shrubs with several feet of space between them.

Aggressive Spreading Perennials

Some perennials quickly crowd nearby plants and steal space underground.

Avoid planting peonies beside:

Mint
Bee balm (unless well controlled)
Obedient plant
Gooseneck loosestrife
Running bamboo

These plants can overwhelm slower-growing peonies over time.

Better Idea:

Choose well-behaved companions such as catmint, salvia, or alliums.

Trees with Heavy Root Competition

Tree roots compete strongly for moisture and nutrients.

Avoid planting peonies beneath or close to:

Maple trees
Birch trees
Willow trees
Large evergreens

Even if sunlight seems adequate, root competition can weaken peonies.

Better Idea:

Give peonies their own bed or open border space.

Plants That Need Constant Wet Soil

Peonies dislike soggy conditions and need well-drained soil.

Avoid pairing them with moisture-loving plants such as:

Astilbe
Marsh marigold
Certain ferns in wet beds
Water garden plants nearby

Keeping soil too wet may cause rot.

Better Idea:

Choose companions that enjoy average garden moisture.

Tall Floppy Plants That Collapse onto Peonies

Some plants sprawl or flop into neighboring plants, reducing airflow and creating mildew issues.

Examples include:

Untrellised morning glory
Overgrown cosmos
Tall floppy asters
Unstaked delphiniums

Better Idea:

Use upright plants or stake taller flowers properly.

Overly Dense Groundcovers

Peonies like mulch and open soil around the crown. Thick mats of plants can crowd stems and trap moisture.

Avoid directly around crowns:

English ivy
Pachysandra
Vinca
Thick creeping groundcovers

Better Idea:

Use light mulch and keep the crown exposed.

Other Plants Planted Too Close

Even good companions can fail if spacing is too tight.

Peonies need room for:

Airflow
Root development
Easy maintenance
Bloom display

Space most peonies 3 to 4 feet apart depending on variety.

Best Plants to Grow Near Peonies Instead

Choose companions with similar needs:

Alliums
Salvia
Catmint
Iris
Columbine
Foxglove
Lavender (in well-drained soil)
Spring bulbs

These add color without overwhelming peonies.

See my full list of Best Companion Plants for Peonies.

Quick Peony Success Tips

For healthier blooms:

Plant in full sun
Avoid crowding
Water deeply but not constantly
Cut back foliage in fall
Avoid frequent moving

Learn more in Multiply Your Peonies This Fall—Here’s How!

FAQs

Can I plant peonies next to hostas?

Yes, if peonies still receive enough sun. Hostas can work nearby but not directly crowding them.

Can peonies grow under trees?

Usually not ideal due to shade and root competition.

Do peonies like crowded beds?

No. They bloom best with good airflow and room to expand.

Peonies are long-term garden treasures, so where you plant them matters. Avoid aggressive spreaders, heavy shade, wet-soil plants, and root competition to give your peonies the best chance to thrive.

Choose neighbors wisely, and your peonies can reward you with beautiful blooms for decades.

Follow my Growing Peonies & Garden Ideas on Pinterest.