I’ve had some issues with my pansies in the past. And although they’re beautiful little flowers that look innocuous they are picky about what’s grown with then.
So let me save you running in to problems with your pansies and having to watch them slowly die off because they’re planted next to the wrong flowers or plants.
Understanding Pansies
Pansies might look tough but they’re just as picky as other flowers. I once planted a border of pansies with some perennials and within a few weeks the pansies had been completely overwhelmed.
They like the temperatures to be between 45 to 65°F and will start to struggle when it gets too hot. They need a lot of consistent moisture but absolutely hate sitting in waterlogged soil. This makes them more vulnerable to plants close to them that either take all the water or block out the sun by growing too large.
And what a lot of people don’t know is that pansies are moderate feeders. They need regular nutrients but will struggle if they’re planted with plants that take a lot of those nutrients from the soil.
I’ve made the mistake of planting pansies with some vegetable seedlings and by the middle of the season they had turned pale, become leggy and were barely flowering at all because they couldn’t fight for nutrients.
So when planning your pansy beds remember they tend to grow about 6 to 9 inches tall. They need the air to be flowing around them to stop disease problems like powdery mildew which means crowding them with the wrong plants can result in disaster.
Plants Not to Plant with Pansies
1. Aggressive Ground Covers
The biggest mistake I see in gardens? Planting pansies alongside ground covers like creeping Jenny or ivy. They will push out pansies, stealing water from them, taking all the nutrients they need and smothering them with their foliage.
A neighbor planted her pansies near some vinca and was shocked when that vinca completely swamped the pansy bed within a month. Those sort of ground covers don’t mess about!
Why it’s a problem:
- Roots fight and beat pansies for nutrients
- It blocks light from reaching pansies
- A lot of ground covers spread too quickly for pansies to establish
2. Tall Sunflowers
I love sunflowers as much as anyone else but you have keep them as far away from your pansies as possible! They will block the sun from getting to other plants but as they grow but they’re also need a lot of nutrients and will take those so your pansies don’t get them.
Why they clash:
- Big differences in height stops the light getting to pansies/li>
- Sunflowers takes nitrogen from the soil
- Sunflower roots are big and aggressive
3. Most Vegetables
Most vegetables make terrible companions for pansies. As vegetables are usually heavy feeders they take a lot from the soil that pansies needs. They also have different water and fertilizer needs than pansies.
Specific veggies to avoid:
- Tomatoes (too tall and hungry)
- Cabbage family (roots fight)
- Squash (they way it grows smothers pansies)
- Corn (too much shade and nutrient demands)
4. Mint Family Plants
Never, ever plant pansies near mint, catnip, lemon balm or other mint family members. I made this mistake when I first started gardening and wound up with mint literally growing through my pansies.
The mint family have extremely aggressive underground runners that will affect everything that’s close to them. Even when they’re grown in pots their roots will escape through the drainage holes and find their way into soil thats nearby.
Why they don’t mix:
- Mint’s rhizomes stop pansy roots from growing and taking nutrients and water up
- Different water needs (mint likes it wetter)
- Mint has a strong scent that can affect how pollinators act
5. Large Ornamental Grasses
Ornamental grasses like miscanthus or pampas grass are terrible neighbors for pansies. The roots of ornamental grasses create stop any close by plants from getting access to water.
The problems they cause:
- Roots take all the water so pansies can’t get any
- Many grasses have allelopathic properties that stop other plants growing
- Mature grasses grow so they create a lot of shade and block the sun to other plants
6. Marigolds
Marigolds and pansies don’t work well together. Marigolds are often recommended as good companion plants for vegetables. But they have allelopathic properties that will stop the growth of certain flowers, including pansies.
I tried marigolds and pansies together in window boxes a couple of years ago, thinking the colors would look good with each other. But after a few weeks my pansies were barely growing and producing fewer flowers while the marigolds had no problems.
Why this pairing fails:
- Marigolds release compounds that can stop nearby plants growing
- Different temperature needs (marigolds love heat, pansies don’t)
7. Large Hostas
Hostas roots and big leaves are just too much in the way of competition for pansies. As hostas leaf out in spring they quickly block the sun from smaller plants.
The compatibility issues:
- Fully grown hostas make a lot of shade
- Hosta roots fight hard for water and nutrients
- They peak at different times (hostas look best when pansies are fading)
8. Chrysanthemums
Fall chrysanthemums and spring pansies have the total opposite growing cycles and care needs. When I overplanted dormant mums with spring pansies I ended up with a mess by summer – the chrysanthemums messed up the pansies just as they were looking their best.
Why they clash:
- Opposite growing seasons make it hard to care for both
- Different needs when it comes to fertilizer (mums are heavy feeders)
- Very different water needs
9. Large Spring Bulbs
Daffodils and tulips might seem like natural companions for pansies as they flower around the same time but the large bulbs fight for the same space that pansies roots need.
Problems with this combination:
- Fight for the same space in the soil
- Risk of damaging bulbs when planting pansies
- Foliage from the bulbs can take over nearby pansies
10. Petunias
Both petunias and pansies have completely different preferences when it comes to the temperature. Petunias do best in the heat but that heat makes pansies melt.
Why they don’t work together:
- Opposite needs for temperature
- In the summer they need different amounts of water
- Need fertilizing at different times
11. Eucalyptus and Other Allelopathic Plants
There are plants like eucalyptus, black walnut and sunflowers that release substances that stop the growth of other plants.
The science behind why they fail:
- Chemical substances get into soil and stop pansies growth
- Even after the plant has been removed the effect can last
- There are issues with shade that just makes them impossible to grow together
12. Most Bamboo Varieties
The running types of bamboo are obviously not going to work as companions for any plant but even clumping bamboo varieties can be far too much competition for pansies. Their elite leave no room for pansy roots to grow properly.
The bamboo problem:
- Very competitive roots
- Make a lot shade once they’re established
- Bamboo litter can land on and stop small plants planted below it from growing
13. Fast-Growing Annuals
Zinnias, cosmos and other summer annuals that grow quickly will overtake and then create too much shade for spring pansies to grow.
I tried interplanting zinnia seeds with pansies one year as I thought the pansies would be done before the zinnias took off. That turned out to be very wrong. The zinnias grew so fast they overwhelmed my pansies by the late spring.
Why it doesn’t work:
- The speed they grow at makes for a big imbalance
- Their blooms peak at different times which create an awkward transition
- Fighting over nutrients as fast growers take off
Good Companion Plants for Pansies
After all thee plants you shouldn’t plant together you’re probably wondering what DOES work with pansies. These are a few you can trust will work:
- Sweet alyssum – doesn’t compete and grows as a very beautiful carpet
- Small spring bulbs like grape hyacinths or crocuses
- Early perennials like coral bells (Heuchera)
- Thick and close herbs like thyme or chives
- Spring blooming shrubs as a backdrop (not too close)
These all have either the same sort if growing needs or naturally look good with pansies without overwhelming them.
Tips for Successful Companion Planting
- Give pansies their own space – they don’t like being crowded
- Choose plants that have the same water and light needs
- Think about flowering times – try to plan so you have plants that give you color as the pansies fade
- Roots – plants with shallow roots are better
- Be aware of height differences – taller plants to the north side
- Use containers to control any aggressive plants you want to include
Final Thoughts
The most important lesson when it comes to planting with pansies? They need to be respected as primary plants, not afterthoughts that you tuck in around more dominating species.
But it’s always good to keep in mind that gardening is an experiment. What works in a Zone 6 garden might not be right for yours. But if you steer clear of these 13 plants it will give your pansies a better chance at reaching their full potential.
