How to Grow Jacob’s Ladder (Polemonium)

So, you wanna grow some Jacob’s Ladder.

This unique plant has gorgeous flowers on top of tall, skinny stems.

It’s also extremely easy to grow and perfect for beginners.

If you want to enjoy a lot of leafy coverage topped off with globes of flowers, this is the plant for you.

I think you’ll enjoy the ease of care and low maintenance it requires.

So, let’s grow some polemonium!

Quick care guide: Jacob’s Ladder (Polemonium)

Plant type	Perennial (moderate zones), annual (colder zones)
Origin	Europe, South America, Asia
Scientific name	Polemonium
Other names	Greek valerian, charity plant, Jacob’s-Ladder, Bluebell, Skunk Weed
Soil type	Clay, loamy, well-draining, organic, plant compost, rich
Soil pH	6-7 (slightly acidic)
Sunlight requirement	Shade, partial sun, full sun
Bloom season	Spring, summer
Colors	Purple, blue, white, green, pink, violet, hybrid, yellow
Max height	3 feet
Max width	18 inches
Low temperature	40F
High temperature	80F
Ideal temperature range	50-60F
Humidity	Medium to high
Watering requirements	Often during first year of growth, spring, and summer
Fertilizer requirements	Low to none
Fertilizer NPK	1-1-1
Days until germination	3-4 weeks
Days until bloom	2-3 months
Speed of growth	Moderate
Hardiness zones	3, 4, 5, 6, 7, 8, 9, 10
Plant depth	0.5 inches
Plant spacing	12-18 inches
Propagation	Seeds, division, cuttings, transplants
Common pests	Gnats, mealybugs, spider mites, leaf miners, snails, slugs, cats, groundhogs
Common diseases	Powdery mildew, leaf spot
Indoor plant	Yes, but not recommended
Outdoor plant	Yes
Grown in container	Yes
Flowering plant	Yes
Beginner friendly	Yes
Care level	Low
Uses	Decoration, color, centerpiece, pathing, bordering, tall plant, edible

What’s Jacob’s Ladder (polemonium)?

Jacob’s Ladder, also known as Polemonium, is a beginner-friendly perennial.

It’s a flowering plant that has over two dozen types and is found all over the world- including Asia and Europe.

The blooms are large, colorful, and gorgeous. They’re cup-shaped with stamens in the middle.

It gets its name due to the rung-like leaves that grow like an alternating ladder.

Polemonium grows tall and skinny, but has huge flowering heads that signal it’s time for spring.

Native to cooler environments and regions, it does well in shade.

• P. reptans is not found in the garden, but in the wild.
• P. caeruleum is bred for the garden, but not in the wild.

Don’t get them confused. It’s Jacob’s Ladder, but P. reptans is a creeping variety.

What does it look like?

The plant is commonly seen with its purple or blue flowers. The original plant P. reptans is native to the US but is going extinct in many states.

So an imported cultivar was brought into the US to help offset the difference.

P. caeruleum is also blue but has some white as well.

This is what you’ll commonly find in the yards of gardeners.

There are also plenty of hybridized types that come in a variety of different strains that can match or complement any plant in your garden.

The rhizomes are sturdy and big giving rise to tall basal foliage. The leaves are either green or white with smooth edges and circular shapes.

Each flower is just about an inch in length and features soft, smooth petals wrapped around the bright stamens. They’re cool-looking even if you use them as a floral arrangement plant.

The difference in the stamen and petal colorations is good enough to bring out the contrasts between the two and it also makes a good companion plant for shorter plants.

Are you ready to grow your Jacob’s Ladder in your garden?

Let’s find out how to plant, grow, and care for Polemonium the easy way.

Popular cultivars

Some of the most popular varieties of Jacob’s Ladder:

• P. reptans (Greek Valerian, creeping Jacob’s Ladder)
• P. acutiflorum (tall plant)
• P. caeruleum (true)
• P. californicum
• P. brandegeei
• P. chartaceum
• P. pectinatum
• P. eximium

Of P. caeruleum, there are even more types like Bambino Lbue, Snow and Sapphires, etc.

Feel free to do some research on each one to see if fits your look. There are numerous hybrids to investigate as well. However, care remains the same.

Note that P. reptans is a creeping variety, which is native to North America. The creeping variety is shorter and likes cooler weather. It’s also a biennial and not commonly found in gardens.

Where does polemonium grow?

Polemonium natively grows in areas that are cooler and have partial shade. They’re an early bloomer and will give your garden some color in the springtime.

In nature, Jacob’s Ladder plants are found hiding under the shade where the soil is moist.

They don’t like full sun and they enjoy conditions that are semi swampy. Think streams and rivers. This is where they grow.

In the garden, you can recreate these conditions to enjoy their tall flowering blooms.

Hardiness zones

Jacob’s Ladder is a perennial in zones 3-8, but can be grown as an annual in lower zones. This plant is most hardy in these zones.

However, it can also be grown in higher zones. Remember that it’s a cool, shade-loving plant.

Hardiness zones 4-10 are suitable for raising polemonium for all-season blooms.

How do you propagate polemonium?

Propagating Jacob’s Ladder is easy.

You can do it from seed, transplants, divisions, or cuttings, so you have plenty of different ways to get this gorgeous plant going.

If it’s your first time and you’re not that experienced, you may want to stick with divisions or cuttings.

This will cut down the time until you see those blooms because starting from seed takes time.

But if you’re looking to reward yourself, perhaps seeing it grow from sprouting to blossoming flowers will make it worthwhile.

Regardless, let’s briefly cover each technique and what you need to know.

Starting from seed

Seed starting can be done with a packet of polemonium seeds available from your local nursery. Follow the instructions on the packet.

Generally, these are the steps to follow for a successful season:

• Wait until 2 months before the last frost date in the spring, especially if you’re in a lower hardiness zone.
• Get a seed starter or egg carton and fill it up with a generic potting mix. You can opt for a fancy brand if you wish, but it’s not important at this part of the plant’s life.
• Drop 2-3 seeds per compartment.
• Water generously for the first time.
• Cover with a humidity dome.
• The seeds will sprout over 3-4 weeks. Keep the soil moist, but not wet.
• Use the humidity dome to increase the water retention over time.
• When the seeds sprout, thin after they develop their first pair of true leaves. One plant per compartment is ideal.
• When the last frost in spring is over with, it’s time to transplant them outdoors. Acclimate them by taking the seed kit outdoors into the sunlight.
• Leave it there for them to acclimate to the sunlight by exposing them to a few hours per day.
• After a week, you can complete their transplant by putting them into the soil.
• Use a high-quality, well-draining garden mix. Each sprout can be placed about 0.5” deep and spaced 12” apart.

Read the next section for specifics.

Note that hybridized varieties may give you some mixed results. If you want exact replicas of the original plant, you should stick with true form cultivars.

Sometimes, surprises are nice though.

From cuttings

You can also propagate it through cuttings. All you need to do is find an existing polemonium and then do a clean cut of about 6” on a stem tip.

Use sterile pruners to cut it. This helps stop bacteria from transmitting between plants.

Take the exposed end and dip it into some rooting gel or powder. This will encourage the plant to take root.

Place the root into a container or the dirt with a fresh, high-quality potting mix.

Water and wait for it to develop leaves. If it does, then it is successfully rooted. Use the same depth and spacing as the original plant.

Starting from cuttings ensures that your offspring’s generation is the same as the original plant, which makes the process of matching different colors easy.

You can guarantee that you’ll have the same true species unless you’re using a hybrid.

By division

This method involves you digging up the plant and making a cut in the rhizome, splitting it in half.

You can put it into 2 or 4 pieces, each with its rhizome and crown.

They should also have their roots.

After that, place each rhizome in individual containers or space them 12” apart in the soil. Use sterilized pruners to cut the rhizome. Keep the crown at the surface level.

Use rooting powder if necessary.

By transplanting

If you want to get it done quickly, transplanting is the key.

All you need to do is buy however many plants you want from the store, then move them into containers or the soil.

Use the same spacing and depth that the original plant came in. Be sure to remove it from the containers carefully and not to damage the roots.

How do you grow Jacob’s Ladder?

Here are some general guidelines for growing and caring for Jacob’s Ladder.

You’ll see that overall care is extremely easy and makes this a beginner-friendly plant. Let’s plant!

Soil

Jacob’s Ladder prefers soil that’s rich in nutrients, most, and well-draining.

Aim for a pH between 6-7 (slightly acidic to neutral) and then supplement with some lime to lower the pH naturally.

Use organic compost to add some nutrients to it if you need to. You can also just use leaf litter that’s free of rot.

Clay helps make the soil more acidic by decreasing the pH without the use of synthetic compounds. You can also use sand or compost to help keep the soil well-draining and loosen tough soil. If you have clumpy soil, you’ll need to till it first.

For container planting, you’ll need to focus even more on using well-draining soil and extra drainage holes on the bottom.

This will provide more drains if one gets clogged. Keep the soil moist, but never waterlogged. A single plant will need up to 18” in diameter.

Use a good potting mix that’s made for containers and has water-retaining properties.

Sunlight

Polemonium prefers shady areas with partial sun. direct sunlight for extended periods will harm and wilt the plant. You may also get shorter plants that are stubbier.

On the other hand, if you never provide enough sun, the plants may be extremely thin and leggy as they crawl towards the light.

Choose a location that’s shady, cool, and allows for slow evaporation of water.

Temperature

Jacob’s Ladder likes temperatures that are cool and breezy.

Keep the range between 50-70F for best results. It can tolerate higher temperatures in the summer, but not extensively.

Supplement with water if temperatures are too high. Keep the soil moist 24/7.

Humidity

This plant tolerates high humidity as it’s native to streams and rivers, but too much humidity will lead to fungal issues and mildew.

Keep airflow good and prune off excess foliage to help evaporate pooled water. Directed seeded plants will do well with a humidity tray or dome. Use a gauge to check the overall percent.

Watering

Keep the soil moist, but never soggy. Don’t let it dry out between waterings.

Measure with your fingertip by dipping it into the first inch of soil. If it’s dry, you waited too long. If it’s wet, you watered too much. Keep it moist at all times.

Account for periods of high heat or rain.

When your plants get very dense, you’ll want to make sure there’s enough sunlight to help drain the water. It can pool and then cause root rot or mildew problems, so keep good sunlight going to help it evaporate.

Additionally, pruning will help get the sun into places where it needs to go so the water doesn’t pool under the leaves.

Fertilizing

Jacob’s Ladder is self-sowing in zones 3-8. It’ll flower and then provide seeds to self propagate itself for next season, so no intervention is needed.

For colder zones, consider it an annual.

You can supplement its growth by using balanced fertilizer in spring, then fall to encourage second blooms.

The plant loves some fish emulsion plant food with high nitrogen to help grow those leafy greens. Look for a balanced NPK rating.

Plant food is optional as it grows well without it.

But if you notice that the flowers aren’t blooming or don’t look voluminous, you can add some fertilizer to help aid their growth. It’ll thank you for it.

Be careful with potted plants because excess buildup can damage the root system, especially if the pot is poorly draining.

Feed when you see new flowers coming out and again after you cut them off when you prune for the best plants you can get.

Pruning

Pruning is necessary to keep Jacob’s Ladder looking good and tidy. This plant requires some regular trimming to keep it from becoming too foliage dense.

Remove faded flowers. Given the right conditions, you can keep it blooming all season.

If you see any stems that droop or lean over, consider adding a trellis or stake to help them stay upright.

Deadheading flowers that have wilted will encourage new blooms by recycling the energy. Cut them back entirely to the base with a clean pair of scissors.

This will keep your polemonium blooming all year and possibly give you a second bloom. It also helps stop any self-sowing. If you have spent leaves, cut those leaves off. This also is a waste of energy for the plant and harbors pests.

Other than that, polemonium is an easy plant to care for. Even if you didn’t do any maintenance, it should still take care of itself.

Companion planting

Polemonium can be companion planted with other plants that enjoy the shade.

This plant will probably bloom first unless you’re growing another early blooming plant like pansies.

But even then, the slower one will catch up and they can complement each other with their gorgeous flowers.

Since there are so many different varieties to choose from, you can pair the colors so they match or complementary plants for a harmonious look in your yard.

Since these are taller plants, choose lower or shorter plants to companion plant with them.

Some good choices are:

• Japanese painted ferns
• Astilbe
• Oriental poppy
• Plantain lilly
• Lady’s Mantle
• Heuchera
• Columbine
• Violets

Pests

Polemonium is hardy to most garden pests. The most common ones you’ll find are leaf miners, slugs, and larger animals like cats.

You can manage these pests with essential oils, slug traps, or sticky traps. Larger animals can be controlled by adding borders or fencing around your plants.

The majority of pests can be controlled by regular doses of DIY remedies. No need for poisons.

Diseases

Jacob’s Ladder is prone to mildew or fungal problems because of the dense leafy coverage. This leads to poor eruption and pools water under the leaves.

Prune regularly and use a well-draining soil. Consider using water-retaining soils and moving your plants, watering less, or using drip irrigation.

Container planting

You can plant polemonium in a container, but just be sure to:

• Use a well-draining soil
• Put a layer of pebbles to help improve drainage
• Put the pot somewhere shady
• Protect it from rain or wind
• Protect it from toppling over by using secure saucers
• Don’t rely on just a few drainage holes, make more if possible
• Don’t overwater!
• Use fertilizer sparingly

Other than that, growing polemonium in a pot is easy.

You can move it around as well to decorate or rearrange your yard. That’s the benefit of having it mobile.

Don’t forget that you can combine different plants in the same pot if it’s big enough.

What can you do with Jacob’s Ladder?

The bests uses for polemonium are endless. It can be used as a decorative pathing plant or at the centerpiece of a garden.

It can be planted in the soil or a pot anywhere there’s shade. It’s also one of the earlier plants to bloom in the season, so you can use it for some early spring flowers.

Jacob’s Ladder can also be snipped and put into a vase for temporary decorations inside your house or as a gift.

You can also use it to bait pollinators like bees and birds into your garden. It also looks great in plant beds for lots of coverage.

Some people also consume Jacob’s Ladder. P. reptans have been used as a herbal aid for cold symptoms.

Common care questions

Here are some questions asked by readers that cover the basics for polemonium care. You may find them helpful.

Can you grow polemonium indoors?

Since it’s a shade-loving plant, indoor growth is a possibility.

If you’re in a warmer zone with hot summers, you can bring it indoors and put it next to a sunny windowsill with partial light coming into your house.

The plant should be OK as long as there’s some filtered light coming in.

Note that keeping it in a container will limit its agility to grow if it’s too small.

Should you deadhead Jacob’s Ladder?

Yes, because it allows spent flowers to be pruned from the stem. This will redirect the plant’s energy.

Rather than wasting it on a spent blossom, it can use it to produce more blooms. Practice deadheading spent flowers, wilting stems, or overgrown foliage.

All of these will focus on what you want most- flowers.

Is Jacob’s Ladder a perennial or annual?

Jacob’s Ladder is a perennial plant that will self sow if left to its own devices.

Provided that it grows in zones 3-8, it’ll bloom from the spring to summer.

Then it’ll produce seeds in the flowers and self-sow for next year.

This plant comes back by itself if the zone isn’t too cold. For colder regions, it’ll be grown as an annual plant only.

When should I cut back my Jacob’s Ladder?

Cut it back when the fall is over and winter’s coming.

During the spring and summer, you should be regularly cutting back any drooping flowers, leaning stems, or leggy leaves. This will help the plant focus its energy on yielding flowers.

Is Jacob’s Ladder invasive?

Jacob’s Ladder will reseed itself, so it doesn’t require intervention to propagate. This doesn’t mean it’s an invasive plant though.

It’s a spring ephemeral as classified by the US FED, which means it’s a short-lived springtime plant. That’s far from being invasive!

It is found natively in areas next to streams or rivers, sometimes where it meets roadside conditions.

If you find polemonium sprouting out of the road, it could be due to years of neglect and the plant grew to these conditions.

Is Jacob’s Ladder poisonous?

Jacob’s Ladder isn’t known to be poisonous and is safe to touch.

However, you should keep pets away and any sensitive individuals who may have adverse reactions. Jacob’s Ladder is regarded as non-toxic by the ASPCA.

Does Jacob’s Ladder need sun or shade?

Polemonium likes shady areas and won’t tolerate direct sunlight for extended periods. It does well with other shady perennials so they can all grow together.

However, it can handle full sun if it’s not too strong which burns it.

It’ll require the right mesic soil for proper growth and needs constantly wet soil- just like a stream.

Is polemonium an evergreen?

Jacob’s Ladder is evergreen in warmer hardiness zones and will self sow. It can be easily divided during spring or fall and grown year-round.

The warmer climates allow polemonium to provide leaves all season, but cooler climates will die back during the cold season.

So it completely depends on where you’re growing it.

Is polemonium deer resistant?

Jacob’s Ladder is fairly resistant to deer because it’s not palatable to them. It can be grown around wildlife to attract bees, birds, wasps, and other beneficial pollinators without being eaten by deer.

How long does Jacob’s Ladder bloom?

Polemonium will bloom from the spring to the summer.

Depending on when you sow, the flowers can be enjoyed for 2-3 seasons (spring to fall or spring to summer).

Mild winters will allow the plant to produce flowers nearly all year. Colder regions will have only a few seasons of bloom.

Is Jacob’s Ladder a native plant?

This plant is native to some states such as Missouri, Minnesota, New Hampshire, Mississippi, Georgia, and around the Great Appalachians.

It’s commonly found in the eastern states next to lakes or streams because it prefers moist soils.

Further reading

Here are some references you may find handy:

• Jacob’s Ladder – Houzz
• Polemonium caeruleum – Wikipedia

Caring for Jacob’s ladder is easy

Now that you know the basics of growing and caring for Polemonium, perhaps you’ll take on the challenge (or lack thereof) of planting this tall, flowering springtime plant!

This plant looks good in its true varieties and hybridized ones with those tall flowers that signal spring is here. Get some plants in those shady parts of your garden.

Pair them with some shorter plants for all-around foliage.

What do you think? Where will you plant it? What will you use it for? Leave a comment and let us know.