How to Grow Agapanthus in Pots (Complete Guide)

So, you want to grow some agapanthus in pots or plant containers.

Those tall, purple and blue flowers. Those dome-like blooms. And those majestic green stalks.

With the added ability to move them around in pots.

How awesome would that be?

Agapanthus can be used for so many things- decoration, pathing, edging, background/foreground plant, centerpiece, and even indoors to brighten up the place.

Thankfully, it’s versatile enough to tolerate being planted in a container. And we’ll talk about everything you need to know to grow it in a pot.

Let’s get started.

Last updated: 11/10/21.

Quick care guide: Agapanthus

Plant typePerennial
OriginSouth Africa
Scientific nameAgapanthus praecox
Other namesLily of the Nile, African Lily
Soil typeFertile, rich, loamy
Soil pH6-7 (slightly acidic to neutral)
Sunlight requirement6-8 hours, full sun
Bloom seasonSpring, Summer
ColorsBlue, white, green, purple, yellow
Max height3 feet
Max width3 feet
Low temperature tolerance40F
High temperature tolerance65F
Ideal temperature range50-60F
HumidityModerate, 50%
Watering requirements1" per week
Fertilizer requirementsLight feeding before blooming season
Plant food NPK5-5-5 or 10-10-10
Days until germination2-4 weeks
Days until bloomWithin the first year of planting
Speed of growthSlow
Hardiness zones5, 6, 7, 8, 9, 10
Plant depth2" from seed
Plant spacing36" between bulbs
Plant withWisteria, hydrangea, daisies, dianthus, alyssum, bird of paradise, coneflower
Don't plant withPlants in the same family
Propagation methodSeed, bulb, transplant
Common pestsGnats, spider mites, thrips, mealybugs, slugs, snails
Common diseasesFungus, gray mold, leaf spot, anthracnose, powdery mildew, root rot
Indoor plantYes
Outdoor plantYes
Grown in containerYes
Flowering plantYes
Beginner friendlyYes
Care levelLow (easy)
Best usesDecoration, houseplant, bordering, background plant, foreground plant, pathing plant, potted plant

What’s agapanthus?

Agapanthus grown in a container.
These gorgeous perennials are known for their dome-like flowers.

If you’re trying to grow agapanthus in a container, you probably already know.

But for those who heard about this gorgeous plant from a friend or neighbor, here’s a brief introduction.

Agapanthus are those tall flowering bi-colored flowers with the signature purple white, and blue petals. They’re tall, majestic, and commonly grow in bunches that look like giant balls of flowers.

The base of the plant is a dome-shaped eruption of green foliage with the flowering petals poking out as its many antennae.

While this plant is pretty common, it’s rarely seen in containers.

They’re native to some parts of the US, which is why they’re so commonly found in the southern parts. They’re also found in Mexico and South Africa, among other countries.

This is where they likely got their nickname “African lily” even though they’re not classified as a lily plant.

So just by planting some in pots, you’re already standing out from the crowd. Put them in your garden, front yard, or around the home as decorative pieces.

The best part about growing agapanthus in a plant container is that it’s easy to relocate them if needed.

So let’s get started already and learn how to raise these gentle giants in pots.

Agapanthus is poisonous

Note that this plant is a poisonous and toxic plant to both humans, dogs, cats, and other animals.

Don’t let your kids or other people touch it or ingest it. Keep animals away from them.

As common as it is, the sap from agapanthus will cause skin irritation and allergic reactions, especially for those that are sensitive.

Always use gloves and proper protective gear when handling, pruning, or trimming agapanthus.

Can agapanthus be grown in pots?

A budding Agapanthus with poison sap.
The sap is poisonous and should never be ingested or touched.

Agapanthus can be planted in pots, provided that the conditions are optimal.

Like any other plant, when the environment is confined to just a small container, the soil’s nutrient profile is critical.

And so is the watering schedule. Both of these need to be optimal for the best plant growth because it doesn’t have access to “unlimited” resources and “unlimited” drainage like it would in the soil.

So while you can grow and raise perfectly large agapanthus in a container, there are some steps to take that differ from planting in the soil.

Follow these guidelines for healthy flowers and a strong, sturdy stem in your African lily.

Pros and cons of container planting

Pros:

  • Easier to move around when winter comes
  • Neat and tidier
  • Easier to manage
  • Relocation and decor can be changed at anytime
  • Sunlight levels can be adjusted
  • Decorative pots can be used to achieve symmetry

Cons:

  • A watering schedule needs to be followed
  • Soil nutrients need to be bountiful
  • Smaller containers will need to be replaced
  • The plant may undergo transplant shock
  • Larger containers are expensive

Check your hardiness zone

Pink and purple agapanthus.
Container planting? Check.

Planting in the right hardiness zone is the first step to ensuring a healthy plant!

You’d be surprised at how many people plant something that’s not the right strain or the right plant for where they live. It doesn’t work like that.

You need to choose the right cultivar specific to your zone so your plant will thrive. This is to ensure a native environment that the plant can tolerate and doesn’t have to struggle.

Most agapanthus grows in zones 8-10, but some cultivars are hardier to cold and can tolerate zones as low as zone 6-7.

  • Agapanthus grown in zones 8 and higher is evergreen.
  • Agapanthus grown in zones 6-7 is deciduous.

Some cultivars are semi-evergreen, so they can be both types and this depends on the zone they’re grown in. Changing the zone changes the type of plant they are.

If you don’t already know your hardiness zone, you can find out here. Get your zone and then choose a cultivar of agapanthus that works for you.

There are about 10 recognized strains and many hybrids.

Each one has an optimal growing zone and varies in color. If you only care about the color of the petals, start with the hardiness zone first, then narrow it down by color.

Don’t choose only by color because if it’s the wrong zone, it won’t be so hot.

When to plant

The best time to plant is in the fall, right before the winter dormancy period.

This allows the plant the most time it can get to develop strong roots over the spring and summer so it can tolerate the winter cold.

The flowers will have been spent and wilted already, so it redirects its energy to the roots and preserves itself for overwintering.

During this low-energy state, the plant can be transplanted into a new container and slowly acclimated to its new environment.

After the winter, the agapanthus will grow again in the springtime and show off its pretty flowers for you to enjoy.

Picking a container

Purple agapanthus planted from a container.
These indigo blooms will be yours.

For optimal growth, choose a container large enough to fit a full size, established agapanthus from the beginning.

It’ll be cheaper overall because you don’t have to transplant it to a larger pot later on when it outgrows the previous container.

Plus, it has more tolerance to water swings and more soil for nutrients.

  • The smaller the container, the more precise with all the soil metrics you have to be.
  • The larger the container, the more forgiving it is overall.

Sure, the smaller pots are cheaper. But think of it as an investment.

If you must use a smaller pot, choose one that’s at least 12” in diameter. It should be at least 14” deep for the plant to establish strong, extensive root systems.

The roots will take up all the space you provide it. So the larger the pot, the longer the root system. This will result in healthy blooms with plenty of colors since the plant has ample roots to collect nutrients and water from the soil.

Note that if you overdo it, you may have some variation in the number of blooms it produces yearly. If the container you chose is too large, you’ll likely see a lot of flowers in the first season or two, but then it tapers off the following years until the roots catch up to the size of the container.

Lastly, you can plant more than one agapanthus per container- provided that it’s large enough.

The material of the pot doesn’t matter. Terra cotta pots are the classic container for this plant, but they’re extremely heavy when you get into the larger sizes.

And they’re expensive, too.

Plastic pots are lightweight and less than 1/3 of the price of terra cotta potters, but they don’t have that potted look to them. It all depends on your preferences.

You can start with a cheaper plastic one for your younger plant and upgrade later on if you wish.

Ceramic pots also look good, but they’re heavy and pricey just like terra cotta. Stone and metal pots also exist.

They do like to be root-bound

A quick note: Choosing a larger container is always good practice for most plants- especially for beginners. It beats upgrading each time the plant outgrows it, which could be very expensive over time.

For agapanthus, you’ll have to upgrade to a larger pot that’s about 2″ larger than the previous one when it outgrows it.

However, if you choose a pot that’s way too big, you may not get optimal flowering either.

This is because agapanthus likes to be root-bound in a way that the roots touch the edge of the container and start to curl. But they don’t like to be cramped and squished.

So this is a balancing act. Don’t choose a container that’s too small, but don’t overdo it either.

For convenience’s sake, a larger container will save you money and reduce effort because you don’t need to keep transplanting it over and over to a bigger pot.

Ensure proper drainage

Bee on agapanthus.
This plant attracts bees and birds.

This is a must. You need to check the bottom of the pot for proper drainage holes.

There should be multiple drain holes, not a single one because it can get clogged and waterlog your planter. I always suggest at least 3 holes on the bottom to ensure drainage even if one gets clogged.

Soil becomes clumpy and hard over time, especially when plant food is added to the mix. Some plastic pots make you drill the drainage holes yourself.

Don’t think of this as a drawback! You can drill them as needed- strategically and multiple so that it doesn’t clog. Adequate drainage is crucial for any plant.

Agapanthus will need it to grow those blue and purple flowers for you to enjoy.

Make sure it’s secure

Whatever planter you choose, make sure that it’s bottom-heavy.

The base of the pot should be sturdy so that it doesn’t tip over at the slightest breeze. If high winds are common in your area, you should ensure that the planter won’t blow over or fall over.

Use a wide base with a secure foundation.

Where to place your container

Your pot should be ideally placed somewhere that receives direct sunlight (anywhere from 6-8 hours daily). It should also be free of drafts, strong winds, and won’t ever topple over.

To enjoy the blooms, you can place the potter where it’ll be visible as a foreground plant. Corners, edges, and patio centerpieces all are excellent places to put the container.

Growing agapanthus in containers

Agapanthus grown indoors.
You can even grow them indoors during the winter.

Here are various suggestions to help you plant your agapanthus in a pot.

Depending on your hardiness zone, cultivar, and your local climate, you’ll have to adjust as needed.

However, these should work as general guidelines for raising this plant in a planter regardless.

So let’s get started.

Soil type

Choosing the right soil shouldn’t be a difficult decision.

This plant isn’t picky about the soil type you use, but it should have some basic necessities for optimal plant blooms:

  • Choose a well-draining soil
  • Use organic or natural soils
  • A loamy soil mixed with compost or manure provides nutrients
  • Use a water-retaining mix
  • Soil pH should be between 5-7 (slightly acidic)

To improve the plant’s drainage, you can add some sand, rocks, or pebbles at the base of your planter to help prevent soil from building up. This will also help keep the drain holes throughput high and stop soil clumping at the base. Agapanthus doesn’t like to have wet feet, as this will cause root rot and fungal problems.

Adding some free-draining loam compost also helps. You can also consider some coarse sand, gravel, or horticultural grit. These all help improve the soil’s draining and keeps your plant from getting wet feet.

Fill your container

Now that you have a platter and soil picked out, you’re ready to fill your pot with the substrate that’ll nourish your agapanthus and feed it!

First, use a 70% rubbing alcohol solution and disinfect the entire thing. You don’t need any more bacterial or fungal infections to deal with later on. You can also leave the planter outside in the full sun for a day or so to kill any pathogens naturally.

After that, start filling it up with the soil. Don’t pack it tightly or press down on it. Just let it fill naturally up to the rim of the container. There should be 2-3” of space from the rim to the soil surface so you have space to water without the water escaping over the edges.

Transplanting

So now you have its new home all set up and ready to go. The next step is up to personal preference on how you want to start your plant.

Note that this plant comes in a variety of different strains, and some are full hardy while others are half-hardy. But don’t get careless just because it’s a full hardy plant.

Even the hardiest plants may need care over the winter if you’re in a colder zone. Since you’re planting in a pot, you can bring it indoors or into a greenhouse.

Planting from transplants

This is by far the most popular method to start. A pre-grown plant from the nursery is ready to go and can be transplanted immediately into its new home.

This plant comes in small containers when purchased from the garden center, and you can emulate it at home by planting it in an identical environment.

The plant is already used to its current conditions, so if you can create a nearly identical environment, it has the best chance of establishing roots in the pot you created.

Plus, it’ll reduce transplant shock as well.

Carefully remove the agapanthus from the original container. Take note of how deep the roots are, how wide the potter is, and how deep it’s planted.

The roots will be complex and extensive at the base- with a bunch of white-yellow runners all clumped together. They may start to separate from the original form and fall apart into the container.

That’s fine, but keep them at the base. Try to keep it from shifting too much when you transplant. Note the shape of the roots before you push them into your container.

Do the same with your container and try to reproduce it.

The roots should be backfilled with compost and slightly compressed to remove any air pockets.

These pockets will create dead zones in your soil and lead to anaerobic pathogens.

However, don’t press down on the soil from the top- only the roots. After you finish backfilling the soil, water generously for the first time. You can top it off with a small layer of mulch for water retention.

Planting from seed

Starting from seed is the slowest method overall and will take time (and test your patience).

But it can also be the most rewarding way of growing agapanthus. Choose a cultivar that grows in your hardiness zone (check the back of the seed packet) and follow the directions.

I won’t go into detail because after sowing the seeds and germination, the process is pretty much the same as transplanting.

Depth

Plant the root ball 2-3 inches below the soil surface. The top of the root ball should be barely covered.

Spacing

Space each plant 8 inches apart. If you only have one plant, put it in the middle of the container so it’s equidistant from all sides. The pot should have at least a 12″ diameter.

Sunlight

Agapanthus requires full, direct sunlight for at least 8 hours a day for the biggest and best blooms.

You can sneak away with just 6 hours, but give it 8 for those long green stems and gorgeous purple petals.

Note the opposite is also true- too much sunlight and you’ll end up burning your foliage.

For those in a higher hardiness zone, such as 9 or 10, you’ll want to limit the amount of sunlight to just 6 hours.

As you can see, it varies depending on where you live and your hardiness zone. This is why I stressed choosing a zone that’s compatible with agapanthus.

Choose somewhere that doesn’t receive light all day or just add artificial shade. Younger plants will need a full year before they produce their first flowers.

Supplement with potash throughout the first year until winter to encourage flower development.

How often should you water agapanthus in pots?

Some water droplets on agapanthus leaves.
Watering matters significantly more when it’s in a pot.

Watering is a balancing act.

Check the soil moisture content with your finger by dipping it in the first inch of soil. If it’s wet, it’s good.

Let it go dry completely before you water again.

This plant is tolerant of short periods of drought, so missing a day or so of water won’t harm it.

When the root system becomes established, agapanthus can handle drought for longer periods. Remember with watering- less is more.

You don’t want to overdo it and waterlog the roots which can lead to fungal problems or root rot.

Container plants also will evaporate and become dry quicker than their oil-based counterparts.

So if you’re growing both in the soil and in containers, your potted agapanthus will need to be watered a lot more often than the ones planted in the soil.

The material of the pot you chose also makes a difference. Terra cotta pots are porous, meaning they have thousands of tiny holes that absorb and funnel out water.

Plastic or metal pots don’t have these pores and will keep the water inside the pot- feeding it to the plant roots.

So you have a bunch of different variables that all affect how much you need to water:

  • The material of the potter
  • The season and temperatures of the week
  • How old the plant is
  • The water-retaining properties of the soil
  • The number of agapanthuses you have per container
  • Mulch, compost, manure, or other supplements

The easiest way is to use a soil meter to monitor the soil saturation levels and water when necessary.

Using your finger only measures the top few inches of soil moisture, but not the root systems which can be saturated with water due to poor drainage.

Mulching

A 1-2 inch layer of organic, high-quality mulch softly layered on top of your soil can help keep the water conserved and stop evaporation. This can help save you a few dollars off your water bill.

How many plants per container?

A single plant requires about 12” of space. If you have a large, 36” diameter container, then you can fit 3 plants.

Use that as a rule of thumb. Smaller plants can do fine in small containers.

But when you replant every 2 years or so, either upgrade to a larger pot or separate the plants into their own.

Fertilizer/plant food

Plant food is well appreciated by agapanthus for large, bigger blooms all season.

You can help aid your plant to produce its flowers for you to enjoy by using the right fertilizer. It prefers a high phosphorus plant food twice a year- once in the early spring and then again in early summer.

Choose an NPK rating of 5-10-5 or similar for best results. Use as directed, as each manufacturer’s feeding regimen varies.

Don’t use plant food that has excess nitrogen (N), because this only gives food to the base foliage (the leaves) rather than the actual blooms. Unless your plant has yellowing flowers, don’t supplement any more nitrogen.

A high potash liquid fertilizer can be applied weekly in small doses during the flowering season to help encourage growth for those who want to maximize their blooms.

Pruning

Agapanthus is an easy to care for and low maintenance plant.

There’s not much to do in terms of pruning or trimming other than removing the flowers that are spent at the end of the season.

These are easy to identify compared to the rest of the growing flowers because they’ll be turning brown and dropping off petals.

Cut them off after they’ve bloomed because they’re just sapping energy from the plant which could be dedicated for the new flower growth.

You can get more voluminous and colorful blooms by cutting the spent flowers as soon as they start drooping (when they’re done blooming).

For evergreen agapanthus:

Cut them at the base of their stalks so you don’t have empty stalks just floating around. The entire stalk is good to remove as it won’t regrow another flower. Remove all dead petals, leaves, stalks, etc.

For deciduous agapanthus:

Cut them back just a few inches from the soil level. Leave about 3-6” of stalk left behind after it blooms. The foliage will automatically die back on its own after the flower has been spent.

Moving to a bigger container

If you started with a smaller pot, you’ll eventually have to move your plant to a larger one so it can develop properly.

You’ll want to check on your roots every 2 or 3 years to see if they’re curling against the edge of the container. If so, you’ll need a larger pot.

Transplant it by gently digging out the dirt surrounding the plant and gently uproot it- just like you did when you first brought it home from the nursery.

You don’t have to upgrade the container right then and there.

It’s OK if the roots touch the edges as agapanthus likes being somewhat root-bound and constricted.

But when you notice the root system starting to curl because they’re hitting the edges of your pot, then it’s time to transplant it to a bigger one.

Do you deadhead?

There’s no need to mess around with the plant’s petals and deadhead. Just prune the entire stalk off at the base accordingly.

  • If it’s evergreen, cut off the whole stalk with the finished blooms.
  • If it’s deciduous, cut until there are a few inches of stalk left behind.

When it’s done flowering, prune off the spent flowers by the stalk. Don’t waste time deadheading it to precision.

When should I repot my agapanthus?

Some Agapanthus large enough to repot.
When it outgrows the container, repot or transplant to soil.

Repot in the fall to a container that’s about 2-3 inches larger in diameter than the current one.

You can divide your agapanthus easily into smaller plants and propagate them.

Fall is the best time to divide and repot because it’s right before their dormancy period and they already have all the established roots necessary from the summer and spring growing season.

Thus, they’re done growing what they can for the winter. After overwintering, they’ll grow again next spring.

Dividing agapanthus in pots

This is a process. The easiest way to divide is to cut the plant base. Find the basal area of the root ball after you carefully uproot the plant.

Cut through the basal area, each piece with its own set of roots and root ball. They should be nearly identical in terms of what they have.

The would that was cut should be coated with a rooting hormone so it can establish roots.

Then each newly divided plant can be put into their new containers in a protective position. Don’t water for a few days until the exposed cut heals. This will help reduce the risk of bacterial or fungal infections.

Keep the soil dry until they become established.

You can add plant food if needed by mixing it into the soil, not by water. The new roots will develop after 30 days and runners will shoot out into the soil.

Avoid dividing in the summer because this can kill your plant. Only divide in the fall.

Here’s a video that shows the process:

When to divide

Divide and propagate in the fall, as this gives your agapanthus plenty of time to develop firm roots for the winter.

Winter care in pots

Deciduous strains are hardier than their evergreen counterparts, so they don’t need as much attention and care during the winter.

They go fully dormant during this time, so they can be left alone outside in the cold. If you’re out in the colder zones (like zone 6), add some protect

Evergreens are sensitive to the cold weather in the winter, so they’ll need to be relocated to a sheltered area in the cold season.

Thankfully, you grew them in pots so they can easily be moved around. That’s the icing on the cake, right?

You can use a greenhouse, or move them indoors during this time.

Don’t let them succumb to the outside temperatures because they don’t tolerate the cold well. These aren’t cold-hardy plants. A sunny spot in your home next to a window works.

Keep the temperature above 50F at all times until winter passes.

Then you can relocate it back outside in your garden.

During this time, you only need to water once or twice a week. Limit watering and only add more water when the soil has gone dry. Agapanthus doesn’t need much in terms of acclimation.

Basic agapanthus care

White Agapanthus blooming.
With proper TLC, you’ll see big blooms.

Here are some tips for taking care of your potted agapanthus.

Because they’re growing in containers, the care is slightly different than if you were to grow them in soil.

However, we’ll cover the gist of what you need to know.

Does agapanthus like sun or shade?

This plant enjoys plenty of direct sunlight for at least 6 to 8 hours a day.

Although some strains may grow in shade, it won’t produce healthy roots and flowers.

You’ll also have fewer blooms per year and they won’t be as big or colorful as a plant that’s had its share of sunlight. Choose a location that has plenty of direct lighting.

Planting from a pot allows you to move your plant around to get all the sunlight it needs.

Doesn’t that make you feel a bit less worried?

Potted agapanthus not flowering

If your potted plant isn’t flowering, try checking the soil profile.

It needs to be higher in phosphorus than nitrogen or potassium.

If you have too much nitrogen, only the green foliage will develop. Supplement with more phosphate if this is the case.

  • Make sure you’re planting in full sun with at least 6 hours of daily sunlight.
  • Add some potash weekly by liquid dose to help encourage flowering.
  • Try moving the container to an area directly under the sun at noontime.

When do they start to shoot?

They bloom in the spring until winter.

New plants will need at least 1 year before they develop shoots and flowers. Established plants will grow shoots and flower every year if the right care is provided.

Do they come back every year?

Agapanthus is a perennial plant so it comes back to regrow flowers and bloom once again if properly cared for.

Sadly, many people buy this plant from the garden center only to keep it until winter then throw it out.

So even though this plant is perennial, many people only raise it as an annual due to poor care techniques.

What to do after they finish flowering?

Cut the entire stalk off with the spent flowers so the plant can redirect energy to the developing flowers and foliage. There’s no need to keep the spent stalks around.

Cut them back to size depending on if it’s an evergreen or deciduous plant, as they require different cut back lengths.

Do they flower more than once?

Yes, agapanthus flowers every year being a perennial plant. They only flower once per season but will flow again next season.

New plants only flower after 1-2 years after they’ve rooted properly. Be patient.

With proper care, you’ll get a flowering season every spring. You can encourage the plant to flower with potash plant supplements or fertilizer.

When the plant becomes established, it flowers every year, once per year.

When do they flower?

Agapanthus begins to flower in the summertime around June to August depending on the cultivar. They flower for weeks at a time before going into winter dormancy.

What can you do with agapanthus?

This plant is extremely versatile and can be used for a multitude of different projects.

A lot of gardeners like to line their pathways or border edgings with this plant.

The tall, flowering blooms stick out of the dense green foliage like feelers trying to get a sense of that fresh natural air and sunlight. You can also mix and match with them complementary colors to create a landscape scene.

With the dominant colors being purple and blue, agapanthus goes well with chrysanthemums, fuchsias, and pansies.

The tall blooms also make this plant well suited for a centerpiece of a focal point in corners.

Here are some suggestions for agapanthus:

  • Placed in front of walls or fences
  • Decorative centerpieces
  • Highlights or foreground plants
  • Background plants
  • Balcony decor
  • An indoor plant (cut the stems and take the entire stalk indoors)
  • Standalone container plant
  • Patio plants

Further reading

Here are some handy resources you may find helpful:

Now you know how to plant agapanthus flowers in containers

Blue agapanthus blooming in a pot.
African lily grown from a pot.

Go ahead and plant these tall, bi-colored perennials in your yard and color it up.

With the portability of planting them in containers, you can move them around as you wish.

No need to worry about if a location is perfect or not- you can tell just by how the plant reacts and relocate it accordingly as needed.

Agapanthus has many different uses and I’m sure you’ll find yours within a few days.

Though, the ability to move it around may make that decision a little tougher.

What do you think? Where will you be placing your agapanthus? Do you have any questions? Leave a comment below and let me know.

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