7 Ultimate Agapanthus Companion Plants & 3 to Avoid

This stunning perennial, known for its vibrant blue or white flowers, can truly thrive when paired with the right plants. Below, I’ve compiled a list of 7 ultimate agapanthus companion plants that promise to enhance your garden’s aesthetics and health, alongside 3 companions to avoid for their well-being.

Good Agapanthus Companion Plants

Nasturtium

Pairing agapanthus with nasturtium is a win-win situation. Nasturtiums, with their bright, edible flowers, not only add a pop of color but also attract beneficial insects that help keep pests away from your agapanthus. This plant’s sprawling habit provides ground cover, which helps maintain soil moisture and temperature, benefiting both plants.

• Step-by-Step Planting Guide:
  1. Select a sunny spot with well-draining soil.
  2. Plant nasturtium seeds directly in the ground, about 12 inches away from your agapanthus, after the last frost date.
  3. Water gently and maintain even moisture until germination.
  4. Once established, nasturtiums require minimal care. Water them during prolonged dry spells.

Interested in more companions? Dive into the post about all nasturtium companion plants here.

Lavender

Lavender and agapanthus make an aromatic duo that’s hard to beat. Lavender’s silver foliage contrasts beautifully with the lush green of agapanthus, while its scent can deter pests. Both plants prefer full sun and well-draining soil, making them garden companions that share care requirements.

• How to Plant Together:
  1. Choose a location with full sun exposure.
  2. Ensure the soil is well-draining; amend with gravel or sand if necessary.
  3. Plant lavender 18 inches apart from agapanthus to allow room for growth.
  4. Water moderately; these plants thrive in somewhat dry conditions.

Learn about more perfect matches in our article on lavender companion plants here.

Rosemary

Rosemary is another herb that pairs wonderfully with agapanthus. This drought-tolerant herb helps repel common garden pests and requires similar growing conditions to agapanthus, making them easy to care for side by side.

• Planting Guide:
  1. Select a spot with full sun and well-draining soil.
  2. Plant rosemary at least 15 inches away from agapanthus to ensure ample growth space.
  3. Water sparingly, as both plants prefer drier conditions.
  4. Mulch lightly to retain soil moisture and reduce weeds.

For more information on companion planting, check out the full guide on rosemary companion plants here.

Geranium

Geraniums are fantastic companions for agapanthus due to their colorful blooms and ability to thrive in similar conditions. They offer ground cover and can help deter pests with their fragrant leaves.

• How to Plant with Agapanthus:
  1. Choose a sunny spot with well-draining soil, akin to agapanthus preferences.
  2. Space geraniums approximately 12-18 inches from agapanthus plants to ensure room for growth.
  3. Water regularly until they are well established, then reduce frequency as both plants prefer drier conditions.
  4. Deadhead geraniums to encourage continuous blooming.

For a deeper dive into companion planting with geraniums, visit our detailed post on geranium companion plants here.

Catmint

Catmint and agapanthus complement each other not just visually but also in their care needs. Catmint’s soft, lavender-blue flowers and aromatic foliage can help repel pests and attract pollinators, creating a more biodiverse garden environment.

• Planting Steps:
  1. Locate a sunny area where both plants can receive at least 6 hours of sunlight daily.
  2. Ensure the soil is well-drained; catmint tolerates drought conditions well.
  3. Plant catmint around 12 inches away from agapanthus, allowing both plants enough space to flourish.
  4. Water moderately until established, and then reduce watering frequency.

Society Garlic

A lesser-known but equally valuable companion for agapanthus is society garlic. This plant’s delicate, purple flowers and garlic-scented foliage can help repel pests, and it thrives under similar conditions to agapanthus.

• Guide to Co-Planting:
  1. Opt for a location that gets full sun to partial shade.
  2. Plant society garlic 10-14 inches from agapanthus to allow both plants adequate space.
  3. Both plants prefer well-drained soil; water sparingly once established.
  4. Society garlic’s foliage can be cut back in late winter to keep the plant tidy and healthy.

Marigolds

Marigolds are not just bright and cheerful; they’re also powerful in repelling garden pests. Their easy care and compatibility with agapanthus make them an excellent choice for companion planting.

• How to Plant Marigolds with Agapanthus:
  1. Select a sunny spot with good drainage.
  2. Space marigolds around 8-10 inches from agapanthus to provide full coverage without overcrowding.
  3. Water regularly until established; both plants do well with minimal watering afterward.
  4. Deadhead marigolds to encourage a longer blooming season.

For more insights, read about marigold companion plants here.

Plants to Avoid Near Agapanthus

Eucalyptus

Avoid planting eucalyptus near agapanthus. Eucalyptus trees can inhibit the growth of nearby plants due to allelopathic substances they release, which can be harmful to agapanthus.

Walnut Trees

Walnut trees produce juglone, a substance toxic to many plants, including agapanthus. The juglone can stunt growth and even kill sensitive plants.

Fennel

Fennel is known to be allelopathic to a wide range of plants and should be kept away from agapanthus. Its strong growth can also compete with agapanthus for nutrients and space.

Companion Planting Chart for Agapanthus

Good Companions	Why Plant Together
Nasturtium	Attracts beneficial insects, provides ground cover
Lavender	Deters pests, requires similar growing conditions
Rosemary	Repels pests, drought-tolerant
Geranium	Offers ground cover, deters pests
Catmint	Attracts pollinators, repels pests
Society Garlic	Repels pests, similar care needs
Marigolds	Repels pests, brightens garden spaces

By carefully selecting companions for your agapanthus, you can create a vibrant, healthy, and sustainable garden. Remember to consider the specific needs and potential interactions between plants to ensure the best outcomes for your garden ecosystem.