Alyssum is a hardy annual flower that can brighten up any garden with its fragrant blossoms and carpet-like growth habit. While alyssum pairs well with many plants, there are some you’ll want to avoid interplanting it with.
We’ll talk about what not to plant with alyssum and why these plants don’t get along in this article. We’ll also provide tips for successful alyssum companion planting.
Why Companion Planting Matters
Companion planting refers to the strategic placement of different plants together in a garden for their mutual benefit. The right combinations enhance growth, deter pests, attract pollinators and improve yield However, incompatible plants compete for resources, spread diseases and inhibit growth
When gardening, it’s important to know about companion relationships. Picking the right plants to grow with alyssum will make a big difference in how healthy and productive your garden is.
What Not to Plant with Alyssum
When selecting companion plants for alyssum avoid interplanting the following varieties
1. Broccoli
Broccoli competes aggressively with alyssum for soil nutrients like nitrogen, phosphorus and potassium. Planting them together leads to subpar yields for both crops. Give broccoli and alyssum separate garden beds.
2. Marigolds
Marigolds give off thiopenes, which are chemicals that stop nearby plants, like alyssum, from growing. Keep marigolds and alyssum in different areas of the garden.
3. Tomatoes
Tomatoes and alyssum don’t thrive when planted together. Alyssum has sulfur compounds in it that make tomatoes taste bad and stop them from growing. Avoid interplanting these two.
4. Petunias
Petunias and alyssum compete for the same pollinators, resulting in less seed production for both flowers. For better pollination, plant alyssum near vegetables instead of other ornamentals.
5. Fennel
Fennel exudes allelopathic chemicals that restrict the growth of nearby plants like alyssum. Give fennel its own separate space in the garden.
6. Roses
Roses and alyssum both attract aphids. Planting them together leads to major aphid infestations. Keep roses and alyssum apart to prevent this pest problem.
7. Corn
Corn rapidly depletes soil nutrients that alyssum needs to thrive. The two battle for nitrogen when planted together, leading to poor growth.
8. Geraniums
Geraniums and alyssum compete heavily for space, water and nutrients. One will become dominant while the other struggles. Separate them in the garden.
Best Companion Plants for Alyssum
While some plants don’t pair well with alyssum, many make excellent companion plants, including:
- Carrots
- Lettuce
- Beets
- Brassicas
- Strawberries
- Peas
- Onions
- Cucumbers
These shallow-rooted vegetables don’t compete much with alyssum for space and nutrients. Alyssum helps deter pests, attract pollinators and suppress weeds around these crops.
Tips for Successful Alyssum Companion Planting
Follow these tips for the healthiest alyssum and companion plants:
- Research compatibility before planting
- Allow adequate spacing between plants
- Avoid overcrowding
- Amend soil with compost
- Use raised beds to separate roots
- Interplant quick-growing greens between incompatible plants
- Rotate plant families each season
- Group plants with similar sunlight and water needs
The Benefits of Thoughtful Companion Planting
By considering alyssum’s companion relationships, you can enhance your garden’s:
- Growth
- Pest resistance
- Pollination
- Disease resistance
- Flavor
- Weed suppression
- Efficient use of space
With mindful companion planting, your alyssum and other plants will thrive together! Avoid unsuitable combinations and reap the rewards of plant synergies in your garden.
Good Companions for Alyssum
A few examples of plants that are good comparisons for alyssum include:
Lettuce: Alyssum attracts beneficial insects that keep pests away from lettuce. Carrots: They don’t compete for nutrients and the alyssum helps keep away carrot flies. Strawberries: Alyssum attracts pollinators that help with strawberries.
Why Compatibility Matters in the Garden
In gardening it’s super important to think about plant compatibility. Why? Because some plants support each other, share their resources and keep away pests.
Others, on the other hand, can hurt their neighbors’ growth, steal their nutrients, or bring in bugs that will hurt them.
That’s why you have to understand and know which plants go together and which don’t. It can make the difference between a garden that’s successful and one that struggles.
So lets look at those that you should avoid planting with your alyssum.
Broccoli and alyssum might seem like a good match but they compete for the same nutrients. This will usually lead to both underperforming or simply not growing at all.
Why Broccoli is a Problem
Nutrient Competition: Both broccoli and alyssum are heavy feeders. They particularly need nitrogen. If you plant them together, they will fight over the same nutrients, making it hard for both of them to get what they need. Pest Attraction: Broccoli attracts pests like aphids and cabbage worms. These can damage broccoli and also spread to alyssum which will cause even more problems.
Marigolds are known for keeping pests away. Which makes them a popular and good choice for gardens. But they can be too competitive for planting with alyssum.
Why Marigolds are a Problem:
Nutrient Competition: Marigolds are heavy feeders and can compete with alyssum for the nutrients they need, nitrogen again being the most sought after. This will leave your alyssum struggling to get the nutrients it needs. Thick Leaves: Marigolds have thick leaves that will block out too much sunlight for alyssum, causing it to grow less and even die.
Tomatoes need a lot of space and lots of nutrients. Again, when planted with alyssum they will often outcompete them and it ends up with the alyssum being deprived of what it needs.
Why Tomatoes are a Problem
Nutrients: Tomatoes require a lot of nutrients, especially phosphorus and potassium. They drain the soil making it hard for alyssum to thrive.Pest Issues: Tomatoes attract pests like aphids and whiteflies. These pests can easily spread to alyssum and do them real damage.
Petunias would on the face of it seem like a good companion. Lots of bright colors together seems like a good match. But they often compete with alyssum for space and nutrients.
Why Petunias are a Problem:
Nutrients: Petunias are another flower that needs a lot of nutrients, especially phosphorus and potassium. This will deplete the soil, making it hard for alyssum to thrive.Pest Issues: Petunias can attract pests like aphids and whiteflies. And again they will spread to your alyssum.
Fennel is notorious for being a terrible companion plant for most plants and flowers. And alyssum is no exception.
Why Fennel is a Problem:
Allelopathic Effects: Fennel releases compounds into the soil that can stop the growth of nearby plants, including alyssum. Your alyssum will struggle to grow and be stunted.Space Competition: Fennel grows large and will overshadow smaller plants like alyssum. This deprives them of both space and the light they need.
Roses may be beautiful but they’re also pretty demanding neighbors. They need large amounts of nutrient and they atrract a ton of pests.
Why Roses are a Problem:
Nutrient Requirements: Roses are heavy feeders that need a lot of nutrients, particularly nitrogen and potassium. This will leave the soil depleted of those, which alyssum also needs, and so makes it hard for your alyssum to thrive.Pest Attraction: Roses attract pests such as aphids, spider mites and Japanese beetles. These pests can spread to alyssum and cause them a lot of problems.
Corn is a heavy feeder and requires a lot of nutrients and will leave alyssum struggling.
Why Corn is a Problem:
Nutrient Competition: Corn’s big need for nutrients, especially for nitrogen, means it competes aggressively with alyssum. It’s that competition that results in poor growth for alyssum.Shade: Corn grows tall and can overshadow alyssum. This limits the amount of sunlight it receives and affect its growth.
Geraniums are tough and easy to grow but not a good companion for alyssum.
Why Geraniums are a Problem:
Nutrient Competition: Geraniums can be heavy feeders. So they will outcompete the alyssum for nutrients.Allelopathic Effects: Some geraniums can release chemicals that stop the growth of nearby plants, and your alyssum will be affected by this.
Potatoes and alyssum don’t make great companions as they need very different soil to grow in. On top of that there are issues with pests.
Why Potatoes are a Problem:
Pest Attraction: Potatoes attract pests like aphids and Colorado potato beetles. And if your alyssum is planted nearby the pests will be all over them.Nutrient Competition: Potatoes are also heavy feeders and will steal all the nutrients your alyssum needs.
Dahlias may be stunning to look at but they’re quite demanding as they grow. And will outcompete and overshadow alyssum.
Why Dahlias are a Problem:
Nutrients: Dahlias have high nutrient needs, particularly for phosphorus and potassium, which can deplete the soil and leave your alyssum struggling.Space Competition: Dahlias grow to be pretty large and so can overshadow alyssum, meaning it doesn’t get enough sunlight and space.
Peppers and alyssum may not be the best neighbors due to both needing a lot of nutrients and being susceptible to similar pests.
Why Peppers are a Problem:
Nutrient Competition: Peppers need lots of nutrients, particularly nitrogen and potassium. Alyssum also need them and so if they can’t get enough they will struggle.Pest Attraction: Peppers attract pests like aphids and spider mites which will also target alyssum.
Mint is a terror in every garden! It dominates wherever it grows. It’s a dreadful companion plant for most plants, alyssum included.
Why Mint is a Problem:
Invasive Growth: Mint spreads aggressively and can quickly take over gardens. It will crowd out alyssum and many other plants.Allelopathic Effects: Mint can release chemicals that stop the growth of nearby plants and stunt your alyssum.
Sweet Alyssum: The Companion Plant You’re Probably Not Growing
FAQ
Does alyssum choke out other plants?
The delicate nature of the alyssum plant means that it doesn’t tend to crowd out its neighbors and kill them. Instead, they tend to creep in around other plants in a beautiful way gently.
What can alyssum be planted with?
Companions: Alyssum is a valuable addition to the vegetable garden and an excellent companion plant for broccoli, Brussel sprouts, cabbage, eggplant, and lettuce.
What does alyssum repel in the garden?
Alyssum is considered an “insectary plant,” as it attracts syrphid flies, lady beetles, lacewings, and parasitic wasps, all of which are natural enemies of aphids and other plant feeding insects. In commercial agriculture, sweet alyssum can help manage aphids when planted en masse.