How to Grow Dramatic Agapanthus in Containers and Pots

The Results We Are Looking For

Agapanthus-Lily of the Nile

Our goal today is to capture the drama of the Agapanthus and utilize it in our container gardens as well as planting beds. There are good reasons why we will want to do this. A combination of our own gardening requirements and the needs of this large and occasionally finicky bulb makes it important that we are able to utilize this choice.

Why We Want the Option of Growing Agapanthus in Pots

Think about the results we want from our container plantings and you will notice how the Agapanthus can help us reach our goals.

A well-draining and compost-rich soil in a container will also fulfill the Agapanthus’ significant need for drainage. And no matter what kind of soil your garden has, you can control the soil in your container. (Terra cotta containers have an additional advantage as they are porous and provide regular drainage. Agapanthus in containers can provide a beautiful presentation and a healthy plant too!)

Agapanthus-Agapanthus africanus

(Agapanthus is the Genus and africanus is the species. The two words together are the name of the plant, the genus is always capitalized and the species-even if it is a proper name-is always in lowercase. That tells us which is which in Binomial Nomenclature which is “Latin for Gardeners.’ )

Large globes of flowers sway on long stems above the long green strips of strap-like foliage. They are elegant and create noticeable accents.

Agapanthus will enhance different styles of gardens; they decorate informal cottage gardens, formal beds with clipped hedges, and contemporary styles as well. They make a desirable cut flower, and the green, draping foliage adds to the various seasons in the garden.

For more information on Agapanthus, one of my favorites, including varieties and sources for buying them, read this.

“Agapanthus-How to Grow the Lily of the Nile.”

The Arresting Agapanthus Bloom

The strap-like foliage is lovely, but the excitement comes from the large globular flowers. You will find plants in many shades of white, blue, and purple. Some will flower in 2-3 colors. Look for white accented with blue or perhaps pink and lavender.

Each flower cluster is a perfect sphere with 20-100 individual tubular flowers.

Why Plant Agapanthus in Pots or Containers

Agapanthus provides us with a large size and dramatic appearance. Their bloom period is also relatively long, lasting for several months in summer and fall. Other good reasons to grow agapanthus in containers are:

• Agapanthus are bulbous plants that flower best when the roots are constricted, and root containment is facilitated by container planting.
• The extra height provided by container planting adds considerable impact to garden beds and accent spots in the garden.
• Agapanthus appreciate exceptional drainage, which pots can provide if your normal soil drainage is not superior.
• In cooler climates, the pots can be moved to enclosed areas in winter.
• The plants are moveable if light conditions change throughout the year.

Agapanthus Colors

It’s not all pale blue and white these days. you can find bicolor varieties in pink, mauve, and blue with white, and breeders are producing more dark blue and purple varieties.

Choosing Agapanthus for Your Container Garden

Agapanthus are large plants that will grow for you over many years. It is worthwhile to select carefully.

• Agapanthus comes in both evergreen and deciduous varieties. The deciduous varieties are most cold tolerant for cool climate gardens. You can use the deciduous versions in beds, where heavy winter mulch can protect them.
• In cooler climates, evergreen varieties in pots can be moved into sheltered places for the winter.

• Select named varieties of tissue-grown agapanthus; these will provide the most predictable performance for you.

Agapanthus for Pollinators and Other Wildlife

If you love wildlife in the garden or have problems with wildlife damage, agapanthus is desirable for your garden. They are appreciated by bees, butterflies, and hummingbirds. Deer seem uninterested in them, and our rabbits are too short!

(Gardeners in some regions beg to differ about deer! If food is in short supply, all bets are off with deer!)

Choosing the Containers for Your Agapanthus

A mature Agapanthus plant will reach between 18″ and 4′ tall and one to three feet wide. This will depend on the cultivar you choose. For a single large plant or 2-3 smaller ones, your initial pot will be about 12′ wide and 9-12″ deep.

A major disappointment in growing Agapanthus is producing beautiful large green leaves and no flowers! A major reason for this failure is choosing a too-roomy pot!

Choose planters not more than twice the size of the plant material you will plant. This will permit the dense root structure that will provide flowers.

Repotting Your Agapanthus

Healthy Agapanthus plants will develop large and dense root material and will eventually be ready to move to a larger pot or divide into several pots. For convenience in repotting, choose pots with larger rims than the base to make it easier to get the solid root material out of the pot. Agapanthus will need repotting about every four to five years.

Signs Your Agapanthus are Ready to be Repotted

Do you see these signs in your Agapanthus?

• The flowers are decreasing, or the plant has stopped flowering.
• Roots are escaping from the drainage holes in the container.

How to Replant Your Potted Agapanthus

Removing the Agapanthus from the pot may be a challenge. This is why we prefer sloping-shaped pots in which the rim is the widest part.

• Run a blade around the inside of the pot to loosen the plant.
• Tip the pot and pull the plant out.
• Cut the roots into sections using a knife blade or a spade to separate the plant.
• Replant where you need the new plants. Note: A single plant section should be in a container not larger in diameter than 12″.

How to Plant Agapanthus

Select well-drained soil with grit or coarse sand included to permit drainage. Any pH between 5.5 and 7.5 is acceptable.

Plant the roots or rhizomes deep enough to cover the roots and place plants about 8″ apart. Fill in the hole, ensuring no air holes are underground and water well.

For help with choosing potting soil, read “How to Choose Potting Soil.“

Maintaining your Beautiful Agapanthus

Light Conditions

Agapanthus grow best in full sun and are reasonably drought-tolerant. In hot climates, partial shade is suitable. In our Zone 10 South Florida garden morning sun and afternoon shade works best.

Water for Agapanthus

The Agapanthus will perform best with moist but well-drained soil. It will not accept standing water. When using containers, ensure that the pot has good drainage. Provide about 1″ of water per week in spring and summer. The plant can dry between waterings in the winter.

If you bring your potted agapanthus indoors for the winter, keep it in a sunny window and reduce the water to about monthly.

Plant Nutrition for Agapanthus

To ensure regular blooms, feed agapanthus twice yearly, directly after blooming or in early spring. Use a low-nitrogen complete fertilizer that includes phosphorus. Look for these numbers on the label 5-10-15 or 8-8-8.

Pests and Diseases

Agapanthus has no serious pest or disease problems.

Problems to look for include:

• Anthracnose-fungi with brown spots associated with wet conditions.
• Gray Mold-fuzzy gray mold, devastating.
• Leaf Discoloration from fungi.
• Powdery Mildew
• Root Rot

Shall I Deadhead Agapanthus?

Any reblooming variety of Agapanthus should be deadheaded to improve performance. Start to deadhead as soon as the earlier blooms begin to fade.

Deadheading (removing spent flowers) will enhance the appearance of the plant and ensure that it will spend all of its energy in blooms.

To deadhead spent flowers, remove the stem close to the base of the plant. Use clean, sterilized, sharp scissors or secateurs as in any other pruning activity.

You can choose not to deadhead some flowers, which will then produce seeds. Note that the new seed-grown plants can differ in color and form from the original parent plant. They will also take several years before blooming.

Disinfect with a material of your choice. Try 70% rubbing alcohol or 10% bleach.

This extra step should ensure maximum blooming from your Agapanthus.

Winter Care for Agapanthus

In zones 8-11, the plants remain in the ground or containers. Mulch well and wrap the pots in freezing events.

In zones 7-6, hardy deciduous varieties should survive under a layer of mulch. The plants do best at temperatures above 40. Allow the leaves to die back naturally, then remove them.

For colder areas, cut back the foliage before the frost period. Dig up the rhizomes, brush off any dirt, and leave them to rest in a warm, dry place for a week. Then wrap in paper (many experts still say newspaper; do you still read the news on paper? If so, you are in luck.) Store them in a cool, dark place at about 40-50 degrees F.

You can bring potted Agapanthus indoors to a sunny window in winter.

Your plants should be ready for you in the spring.

Winter Care and Hardiness Zones

In zones 8-11, agapanthus plants can safely live outdoors in winter. There are a few varieties hardy to zone 7. In zone 8, cut the plants back near the ground and cover them with at least 3″ of mulch. Remember to remove the mulch in spring so the plant can grow.

A few agapanthus hybrids, including the Headbourne variety, are said to be hardy in zone 6 with mulching.

Do you know your plant hardiness zone? Here is the USDA plant hardiness zone map. The plant hardiness map is a quick and free tool; just enter your location.

Companion Plants for Agapanthus

With Agapanthus, you can use any sun-loving annuals, perennials, and shrubs. Consider daylilies, dianthus, and daisies. Also, consider hydrangea or butterfly bush. The many tubular flowers of Agapanthus will attract butterflies and hummingbirds.

Use the striking globe shape with other interesting shapes to set them off. Try them with tall ornamental grasses as well as clipped hedges and topiary.

Use Agapanthus later in the season near roses and other mid-season bloomers to extend the season of color.

When to Replant Agapanthus

Agapanthus perform well when slightly crowded or pot-bound. Agapanthus often benefit from repotting every four years. Deciduous agapanthus may last 6-8 years between replanting.

When you remove the plants from the nursery pot or your initial container, look for a healthy swirl of rich white root material.

How to Repot Agapanthus

To repot your plant, carefully remove the plant from the pot by cutting around the edge, then press gently and pull the plant out. This can take a few tries. You can place the root on the ground and use a spade for the main cut.

Trim the plant near the root and trim any dead material. Split the root ball with a large knife. Then, replant the smaller cuttings you have created in suitable-sized pots.

Best Season to Repot Agapanthus

This will work best in spring or early fall. If you can repot in the fall, your opportunity to have new blooms the next year is best. Spring-divided plants will grow well but may not rebloom that season.

Choose containers you can handle in your garden. In our subtropical zone 10 garden, we like heavy, hard ceramic pots. They are heavy and not disturbed by South Florida’s high summer winds, and the dense glazing saves water. Porous clay pots have the advantage of being porous, and this is a benefit if you have concerns about good drainage. (You will water them more often; however, they are beautiful and reasonably heavy.)

On the other hand, we have neighbors who are expert gardeners who have recently declared that upon reaching the age of 80, they will only use plastic because they can move them.

Knowing your objectives and using the best material for yourself is a good idea!

More General Information about Agapanthus

If Agapanthus do not Bloom

Most agapanthus plants will flower the first year in your landscape. A named variety of agapanthus is commonly developed from tissue culture. Seed-grown plants may take several years longer.

What will cause the plants not to bloom?

Overwatering will cause the plant to produce beautiful foliage but no flowers.

Sometimes the stress of transplanting will cause the plant to not bloom in the first year.

Agapanthus perform best when their roots are compact; they may not bloom when they have too much room or are too tightly together. If a blooming plant stops blooming, it may need division.

Lack of sunlight and nutrition may prevent blooming.

Enjoy these beautiful plants.

Summary,

These beautiful plants should provide us with pleasure every year and, over time, with new plants too!

Here is how to find your USDA Plant Hardiness Zone

Also, here are the first and last frost dates.

In each case, just add your zip code for information.