How to Grow Lily Flowers
There’s no doubt that lilies are one of the most popular flowers in the world. They come in a great range of colors, sizes, and shapes, and it’s sheer joy to grow them in one’s garden.
These perennial plants grow from bulbs, seeds, bulbils, bulblets, scales, and many other methods, and go on blooming every year once planted successfully, even with minimal upkeep, and delight the onlookers’ eyes.
Published: October 18, 2022.
How does Lily Look?
The height of a lily plant ranges from 2 to 8 feet. The Lily flower has six tepals (or petals) that are either plain or marked with freckles, color strokes, or bars. The flowers may be in a variety of shapes, including a trumpet, bowl, bell, or even may be flat.
Some lily varieties also have flowers facing downward with recurved (turned backward) petals, while some others may face upward. Flowers can grow singly or in clusters.
The stem is tall and erect and has long, narrow leaves shaped like a spear. Most varieties are immensely fragrant. As mentioned earlier, lilies come in a range of colors, including white, pink, orange, red, and bright yellow or golden.
Identifying ‘True’ Lilies
Many plants are named “lily” but are not actually lilies. Growers should learn to identify “true lilies” that belong to the genus “Lilium” in the Liliaceae family and have onion-like bulbs.
For example, Daylilies (Hemerocallis spp. Asparagales family) are not true lilies, though appear much like lilies. The main difference is that they have many leaves growing from a crown. True lilies, on the other hand, usually have only a single stem or shoot growing from a bulb. Other varieties are calla lilies, lily-of-the-valley, water lilies, canna lilies, and peace lilies which are not true lilies.
The RHS Lily Group and Species to Choose
The Royal Horticultural Society, in the mid-1960s, formed the RHS Lily Group to classify lilies and provide lily lovers with the correct information for planting lilies.
According to the RHS Lily Group, around 100 botanical species and hundreds of hybrids of lilies can be classified into 9 divisions depending on similarities in flower form and aspects, bloom times, hardiness, parentage, and growth habits.
There are total of 9 divisions noted by Roman numerals. This classification can help remove the confusion between “true lilies” and other similar-looking non-lily flowers.
Each division consists of several species, subspecies, and hybrid cultivars. Plus, every year, new hybrids are added to the collection.
However, when it comes to which species to choose for growing, growers don’t have to worry about remembering all 9 divisions because most popular varieties come in the Divisions I and VII. These are Asiatic and Oriental hybrids. However, there are some others growers won’t afford to miss, like the heady Trumpets in Division VI or the new stunning hybrids in Division VIII, such Orienpets and Asiapets.
Also, there are other beautiful options for naturalized areas, like the North American species and hybrids in Division IV and the True Species in Division IX.
Here are the 9 divisions:
Division I – Asiatic hybrids
Division II – Martagon hybrids
Division III – Euro-Caucasian hybrids
Division IV – American hybrids
Division V – Longiflorum hybrids
Division VI – Trumpet and Aurelian hybrids
Division VII – Oriental hybrids
Division VIII – Other interdivisional hybrids
Division IX – Species and cultivars of species
And here are the details of a few popular varieties.
Asiatic Lilies
Asiatic lilies are one of the shortest species of lilies, growing only 2-3 feet tall, and flower first in early summer months, i.e., in May or June, just after peonies. They are hardy in Zones 4 to 9. They are the earliest to grow and bloom.
They come in a variety of colors, including bright yellow, red, pure white, orange, and pink, and their flowers face upward. As long as they are grown in well-drained soil, they don’t have any problem.
Although they are not fragrant, as intense breeding has reduced much of their fragrance, they make the garden look stunningly colorful.
Trumpet Lilies
If users want to enjoy the fragrance of lilies, they should choose this variety. They produce many blooms (12 to 15 per stalk) and have a pleasing scent. The flowers tend to be smaller and more closed than that of other lilies, thus shaped like a trumpet. They are hardy in Zones 5 to 9. They can be classified into two categories:
1. Easter Lilies (Lilium longiflorum): These fragrant lilies are more popular as a holiday plant and are grown indoors. As their name indicates, they are usually forcibly made to bloom by Easter, i.e., in March or April. When grown outdoors, they do well in the warmer regions of North America, where they can be planted in the garden after they finish blooming inside the house.
2. Aurelian hybrids: These are taller than the two varieties and can even grow up to 5 feet.
Oriental Lilies
Oriental lilies resemble trumpet lilies in having a lot of blooms with a pleasant fragrance. They grow tall, i.e., up to 4 feet, and look stately. They have a tendency to grow more slowly and usually bloom by the time when Asiatic lily flowers fade, i.e., in mid- to late summer.
Turk’s Cap Lilies (Lilium martagon, also known as Martagon Lilies)
Martagon lilies grow 3 to 4 feet tall and have delicate 3-inch flowers with recurved (curved backward) petals. They get up to 20 blooms on each stem. These are hardy in zones 3 to 9.
Tiger Lilies (Lilium lancifolium)
This is a stunning variety growing 3 to 4 feet tall with flowers that have large, pendulous, spotted, recurved petals. These are very hardy (zones 3 to 9) and go on multiplying to become large clumps over time.
They are very easy to grow, thrive in almost any condition, and produce a dozen or even more flowers on each stem. Their colors are generally warmer such as orange, golden yellow, and red.
Rubrum Lilies (Lilium speciosum var. rubrum)
Like Tiger Lilies, Rubrum lilies too have recurved petals. However, their color range is cooler such as deep pink and white. They also have a very sweet fragrance.
Chinese Lily (Lilium regale)
This is one of the easiest to grow white lilies. It produces shiny white, trumpet-shaped flowers with golden yellow centers and a pleasant fragrance. It can even be grown in containers. These bloom by June and reach a height of 1.5 meters.
Hybrids of Asiatic and Easter lilies are named LA lilies, while of Trumpet and Oriental lilies are known as Orienpet lilies. Growers can go through the catalogs of the gardening retailers and see which ones they like the best.
Blooming Time of Lilies
Some varieties of lilies may bloom in late spring, while some others may bloom from early summer to fall, depending on the type. If growers blend all these varieties carefully in their garden, they can enjoy the colorful blooms through the entire period from spring to first frost.
Planting
When to Plant Lilies?
In most regions, it’s best to plant lily bulbs in late summer or early fall, a few weeks before the freezing temperatures of the winter start to appear, so that they can get time to develop a few new roots before the start of winter. Bulbs planted in the fall will develop a good root system in the spring. The winter chill will also benefit the bulbs to produce big blooms.
However, it’s difficult to obtain bulbs at this time from commercial growers, so it’s a good idea to grow one’s own stock from seeds.
In regions that get especially harsh winters, it’s best to plant lilies in spring instead, as soon as the threat of frost is over.
If one is going to plant lilies in containers, one should do so in early summer.
Growers should buy the bulbs close to planting time because lily bulbs don’t go dormant. Unlike many other plants’ hardy bulbs, lily bulbs are imbricate, meaning they don’t have the moisture-retentive papery covering known as “tunic”, so, they can dry out quickly in storage and deteriorate over time.
Hence it’s not advisable to buy bulbs in the fall and then wait till spring to plant them. However, if the bulbs arrive in colder months, there is an option to pot them and keep in a cool but frost-free spot and then carefully plant them out in the spring or next fall.
Growing in the Ground
Choosing and Preparing a Site to Plant Lilies
Growers should select a site where the soil drains well. This can be found after a good rain, by finding a spot that dries out first. If lily bulbs stand in logged water, they rot; therefore well-drained soil is essential.
Growers should enrich the soil with garden compost or leaf mold to facilitate water retention in hot weather and sharp coarse sand or gravel to promote good drainage. If for some reason, the soil has become totally unsuitable for growing lilies, growers have the option of growing them in raised beds where they can be supplied with good drainage and specially-mixed compost.
Many other varieties also do well in containers, especially if the pots themselves can be shaded so as to keep the roots cool.
[Note: Growers should never plant lilies in poorly-prepared soil. If a hole is dug in unprepared clay soil, the grit or crocks placed at the bottom will be totally ineffective and water will accumulate in the sump causing death of the bulbs. Growers should make sure they improve the soil and drainage of the entire area and not just the hole.]
In general, lilies are happy when their tops get a lot of sun and roots are shaded by adjacent plants. Lilies need 6 to 8 hours of direct sunlight per day to produce dependable blooms. If the top part of the plant is in shade, the stems will try to lean towards the sun or get gangly and fall over in the attempt.
But growers should make sure that the nearby plants providing shade to lilies’ roots should not be very vigorous or spreading since lilies cannot compete well with such strong neighbors, e.g. peonies. The shade should not be too heavy and some direct sunlight for a part of the day should reach the plants. Many varieties do well in the cool and sheltered conditions of woodland gardens or in gaps between rhododendrons.
It should also be remembered that varieties like pardalinum, lancifolium and Martagon are happy in dappled shade and generally self-seed to form an amazing colony under deciduous trees. They are also perfect for naturalizing.
Most of the lily varieties are happy with acidic to neutral soil; however, some prefer alkaline soils, e.g. Madonna lilies (L. candidum) and Tiger Lily or Henry’s Lily (L. henryi) are lime-tolerant.
Planting
Growers should loosen the soil up to 12 to 15 inches deep. The depth of the hole should ideally be 3 times as much as the height of the bulb. Deeper planting stimulates the developing stem to send out roots to help the plant stabilize and even may eliminate the need for staking.
Also, lily bulbs remain cool in increased temperatures when planted deep. But there is an exception to this and it’s L. candidum which should be planted much more shallowly i.e. just below the surface. Before placing the bulb in the hole, growers should place a layer of stones or pieces of old crocks in the bottom, above which they should add a dressing of coarse gravel.
Then the bulb should be placed in the hole. The pointy side of the bulb should be upward. If the bulb has previous roots, growers should make sure they are not damaged. Once the bulb is placed in the hole, growers should fill the hole with soil and lightly tamp. Position should be clearly marked to avoid causing accidental damage to the spring shoots.
Bulbs should be spaced apart three times their diameter (this is typically around 8 to 18 inches, depending on the variety).
Planting lily bulbs in groups of 3 to 5 is advisable for achieving visual appeal.
Growers should water the bulbs generously at the time of planting.
Protecting Newly-planted Bulbs from Excess Winter Rain
During the first winter, growers should preferably try to protect the newly-planted bulbs from excess rain. They can do this easily by covering the planting spot with some sort of cover like a plastic sheet or even a large pot.
This should be secured well to avoid getting blown away in winter storms. If growers’ area receives very high rainfall or they grow some more challenging species, they should preferably do this every winter.
In late winter, however, the cover should be removed, as this is the time for new shoots to emerge. This is also a good time to feed the plant with a little bone, blood, and fish, or a similar fertilizer, and apply a leaf mulch.
How to Care for Lily Plants?
When active growth is taking place, growers should water generously, particularly if rainfall is less than 1 inch per week.
Growers should avoid wetting the foliage as damp foliage can result in various fungal growths. Species like L. papilliferum and L. parvum are more prone to this than others, and should be avoided in areas receiving heavy rainfall.
To keep the roots cool, lily plants should be mulched well. The mulch should be moist and not wet.
Growers should apply a high-potassium liquid fertilizer every couple of weeks from planting till 6 weeks after flowering. They should also apply a thin layer of compost each spring, and then a 2-inch layer of mulch.
If lily plants are tall, growers should stake them.
Lilies don’t bloom more than once per season. But growers can remove faded flowers so that plant’s energy is not wasted making seeds.
After the plant blooms, growers can remove only the stem, but they should not remove leaves until they turned brown and died down in fall. It’s extremely essential to avoid cutting back the leaves till the end of the season because they provide nourishment to the bulb for the next season’s bloom.
Growers should cut down the dead stalks in the late fall or early spring.
Before winter, 4 to 6 inches of mulch should be added, just to postpone the ground freeze and enable the roots to continue growing. They should leave the mulch till spring once the last harsh frost passes. They should check their local frost dates.
(If the grower’s region is not covered with snow, they should keep the soil moist in winter.)
When lily shoots start growing in the spring through the mulch, growers should start removing it slowly.
Growers should separate plants every 3 to 4 years since new growth starts in the spring. They should just lift the plants and separate the clumps. The new bulbs should then be replanted adding some compost.
Growing in Pots
Many varieties of lily do extremely well when grown in pots. L. speciosum is a good example of this. In fact, planting lilies in pots has several advantages including being able to bring them in the house or conservatory to enjoy the beauty and fragrance of the flowers.
However, growing in pots can also be challenging in the sense that it demands more time and some skill to identify the correct amount of water and food. In pots too growers should maintain excellent drainage. Hence raising the pots off the ground using bricks, paving stones or pot feet is a good idea.
All the main principles of growing lilies in the ground apply to growing in pots too. These include well-drained compost, generous amount of water and cool roots.
Pots
Clay or plastic pots are fine. Clay pots keep roots cooler and help avoid excess water accumulation because some amount evaporates through their sides.
Their disadvantage is that they are quite heavier than plastic. However, potting technique and aftercare are the same in clay and plastic pots, albeit it’s better to use more freely draining compost in plastic pots so as to avoid waterlogging.
Under-potting
The size of the pot should be suitable to the bulbs and allow a little growth. Over-potting can be a big mistake.
Lilies when planted in the garden do best in conjunction with other plants, as other plants’ roots absorb excess water and the soil too contains a lot of fungi and other microorganisms that maintain balance and healthy conditions. However, when grown in plants, if lily bulbs are surrounded by soggy compost, they’re sure to get destroyed. Therefore under-potting is advisable.
Compost and Fertilizers
A layer of crocks should be placed at the bottom of the chosen pot above which a dressing of coarse grit is to be added. Now a layer of the selected compost should be added. An overall good compost contains three parts of ericaceous compost, one part of coarse grit and a little perlite.
Growers can add a little slow-release fertilizer. However many growers prefer a liquid fertilizer during the season, beginning with a general feed and then switching to a high-potash feed for the second half of the growing season. This method is good for lilies like L. auratum and L. speciosum, but can also be easily adapted for any species with its special needs added, e.g. lime may be added for L. henryi or loam for species like L. bulbiferum which are happy with a slightly less humus-rich growing medium.
Planting Lilies in Pots
Once the pot is ready, the grower should check the bulbs and remove any rotten scales or roots, dust and any prominent wounds with sulfur which can prevent further rotting, and then place the bulbs on the compost. Healthy roots should be spread out without damaging them.
The only task remains is to re-fill the pot up the rim, keeping adequate space for watering and water, and then label it.
If growers plant during fall or winter, they should let the pot drain and dry out a little so as to keep it just somewhat moist. This should be checked with one’s finger.
Sealing the Pot
After planting in this way, growers should seal the pot in a plastic bag of appropriate size to keep the compost at a constantly moderate moisture level and let the bulbs have a good scope to establish a basal root system before developing the top growth in the spring.
Growers should place the sealed pot in a dry, frost-free place like a shed or garage.
This is also actually a good way to store potted plants every winter.
When Top Growth Appears
By early spring, before the top growth appears, growers should remove the plastic bag and place the pot in a sheltered spot. The bag can be used again, so, they should keep it. It’s important to remember to avoid over-watering while the new bulbs have a few roots.
Pots should be checked frequently. Once a good growth starts to appear, growers can carefully increase the level of watering and liquid feeding, when they are sure that a good root system has been developed.
Growing from Seeds
For growing lilies from seeds, one needs a lot of patience, because flowering takes at least a year. Some species take two to three years while some others take even 7 years for flowering.
Seeds usually ripen in late summer and should be collected on a dry day, around 8 weeks after the last blooms.
When the pods age, they swell significantly and change color from green to brown, and then split open. Mature seeds that are dry, dark and firm can then be seen inside.
Species to be Chosen
When it comes to ease of growing, L. regale is especially easy to grow from seeds and one of the most beautiful and fragrant lilies.
Other species that flower quickly from seeds are L. pumulum, L. cernuum and l. amabile, especially if they are left in their seed pots.
The fragrant L. sargentilae does flower when grown from seeds, but a little stunted in its second year. However, after that when grower moves it out, it develops into a lovely plant.
L. longiflorum and L. formosanum are the species that grow well from seeds in a heated greenhouse and flower within the first year. They are also very fragrant.
If growers approach seed firms, they can usually get Mixed Asiatic Hybrids and Mixed Aurelian Hybrids which start blooming within 2-3 years and offer a range of colors. They too are easy to grow and are lime-tolerant.
Sowing
Different lily species seeds germinate in different ways, and the way the changing temperatures trigger their germination also varies. Due to this, some lily growers apply a quite elaborate method of germinating lily seeds. This is as follows.
Growers apply three months of warm, moist environment followed by three months of cold temperatures. For this, growers should mix seeds with around 2 cups of moist peat moss and place them in a container or bag, and cover loosely.
They should store this mixture in a dark, warm spot. They should check it biweekly to make sure the peat hasn’t dried out and add water as required to keep it moist.
The seeds will swell and look like small bulbs. At this time, growers should place them in refrigerator for around three months. The peat moss should be kept moist and their temperature should be maintained between 45 and 55°F during these three months.
In practice, however, growers can get good results simply by sowing seeds once they get them and letting the natural change of temperatures do all the work of triggering germination. This applies to temperate regions.
However, the North American species and hybrids seem to do well when sown in early fall so as to give them a period of cool night temperatures, which is important for their germination. Then in late winter or early spring, the first leaves will show.
Containers
A 5 inch (125mm) plastic pot is perhaps the most suitable size for around ten lily seeds. Some growers even choose a 6 inch (150cm) pot which offers more growing space to the seedlings and thus more time to strengthen before being disturbed for transplantation. If growers wish, they can use clay pots too.
Compost
As mentioned earlier, lily compost should have good drainage i.e. it should have an open texture. As most lilies perform well in a neutral or slightly acidic compost, it’s best to base the compost on an ericaceous or lime-free blend.
Lily growers quickly develop their own favorite mix. A mixture that has proved to perform well for most species is one part of coarse lime-free gravel, one part gritty lime-free garden soil, and one part of fine composted pine bark.
Another simple alternative is half coarse lime-free gravel and half ericaceous mix.
A few species even prefer a little lime in their soil, like L. pyrenaicum, L. pomponium, L. henryi, L. chalcedonicum, L. candidum, L. bulbiferum and L. amabile.
How to Sow
Growers should place a layer of broken crocks at the bottom of the pot. Then they should add a layer of coarse gravel. Then they should fill the pot with compost up to the internal level mark and then gently tamp.
Now they should sow the seeds separately atop this compost. Deeper sowing can lead to seedlings being too close and getting damp. The embryo will appear as a thin line on the seed when held against the light. The best method is to sow on the edge with the embryo downwards so as to protect it from damage.
If growers have obtained a lot of seeds of only one species, they should use either several pots, a deep tray (a normal tray is not suitable for lilies), or can even sow them in the garden in a row or under cover.
After this, growers should top the pot with the same compost at around 1cm of thickness and tamp lightly. If the pots are to be left outside, topping them with grit rather than compost is a better idea to protect the seeds from being washed out by heavy rain.
Label the pot with the name of lily and any other details you may think necessary, such as the date of sowing and the number of seeds.
When the pot is ready in this way, growers should keep it in a bowl of water and let the water soak the compost by capillary action.
Now growers should let the pots drain and then place them outdoors, in a sheltered spot that gets bright, but indirect light and should keep the soil moist but not wet. Some growers prefer to cover the pots with a cold frame or cloche to protect them from slugs, very wet weather and pests. Or they seal it with a twist tie in a clear plastic freezer bag.
This ensures safety and moisture until germination. A shed or garage is best for these pots and they should be checked regularly.
If growers have sown seeds of tender species like L. neilgherrense or L. primulinum, the pots should be kept in the shade in a place like a cool conservatory with the least temperature of around 10°C.
Epigeal and Hypogeal Germination and Aftercare
Lilies germinate in two ways: epigeal and hypogeal. In epigeal germination, an onion-like seed leaf develops upon germination. This may take place a few weeks in species like L. regale or even be delayed e.g. in L. carniolicum.
Others such as L. martagon and most North American species like L. pardalinum grow initially below soil, and their leaf doesn’t show until the next spring. This is known as hypogeal germination.
Other kinds of germination are also shown by a few species. It helps to know the type of germination in order to understand when to check the seed pot.
Once the seedlings appear, growers should remove the bag if they have used it and then transport the pot to an appropriate growing position. The pot should be kept cool and nicely moist in hot weather. If growers are successful in growing their seedlings in winter for their first year (in a heated greenhouse), the plants will establish much sooner.
Some Tips for Seed-growing
- Overwatering should be strictly avoided and the compost should be prevented from getting soggy.
- Liquid feeding quickens the growth, but without feeding an even better root system and plants that are more disease-resistant may be achieved.
- Growers should keep a keen eye on greenfly, snails and slugs which love to eat tender lily leaves.
- Young lilies should be kept in the pot till they become a good size, i.e. up to around two years. Then they should be potted in a similar compost with a slow-release fertilizer or should be planted out in well-drained soil or raised bed.
- Growers should never abandon a bare seed pot till at least three years, since certain lilies can delay germination till they pass through many seasonal cycles.
Pests and Diseases
Viruses
Viruses are spread by aphids and may be problematic, though some of the cultivars are virus-tolerant.
Gray Mold
Gray mold can sometimes occur, particularly in a cool, wet spring or summer. To avoid this, lilies should not be crowded and ample air circulation should be allowed.
Snails, Slugs and Red Lily Beetles
These may sometimes occur. Snails and slugs love eating emerging lily shoots in the spring. Growers should remove them as soon as they’re spotted.
The 8mm long striking red beetles can occur anytime from March to October. They eat up leaves and leave black dung behind, from which growers can know their presence.
But the beetles themselves are hard to spot. Growers can best protect their plants against these pests through vigilance. They should watch out for eggs and larvae on the backside of leaves and remove them quickly once they occur. In case of severe infestation, growers may need to spray an insecticide. But they should avoid spraying it on flowers as they may pose a danger to pollinating insects.
Groundhogs, Voles, Rabbits and Deer
These may eat whole plants. Planting the bulbs in wired cages can protect the plant from getting eaten.
Harvest
Lilies are awesome cut flowers to be displayed in vases. However, growers should avoid cutting off more than a third of the stem. If they cut more than that, the plant’s vigor and longevity can be reduced, since the plant needs leaves to produce food and thus energy.
If growers are strictly growing lilies for cut flowers, they should consider planting them in a specific cutting garden, where they can plant fresh bulbs every year.
While cutting lilies, growers should choose those with buds slightly open with a little color showing. Buds located higher up will open as the bottom ones fade.
As soon as, growers bring the lilies inside, they should trim the stem ends around an inch, cutting it diagonally with a sharp knife.
If growers are worried that the orange pollen might cause stains, they can just cut off the stamens in the flowers’ centers.
A good lily arrangement can last for two or more weeks. The water should be changed every few days.
Flower’s life can be prolonged by adding cut-flower food to the water. Lilies need only half as much food as required by other flowers.
Risks
As such, lilies are safe for humans. However, if the growers have cats in their homes, they should preferably avoid planting lilies because all parts of lily plants are toxic to felines. If growers suspect that their cat has ingested any of the plant’s parts, they should immediately contact their veterinarian.