Torch lilies are truly sun worshippers. It owes its nickname to the archetype Kniphofia uvaria. We'll show you how the rocket flower can really take off in your garden.
The torch lily (Kniphofia) shines brightly in the garden. Colored red, as the name suggests, it towers up like a torch on the bushy leaves. Their nectar is drinkable and is used in creams and ointments. The torch lily is popular with bees and butterflies because of this nectar. Important to note is their limited winter hardiness. It survives the winter best in mild locations and in front of protected south faces. Here we explain what else you need to know about planting and care.
Torch lily: origin and properties
Torch lilies, also known as rocket flowers, are a genus of plants from Africa within the family of asphodeloides (Asphodeloideae). Many people are likely to find another member of this family, namely the true aloe (Aloe vera), to be known. Its natural location offers it a Mediterranean climate under the blazing sun. From the coast up to the low and high mountain ranges, it thrives on grassy slopes and on the banks of streams. In the cold months, she stands in seeping wet soil, which is always supplied with fresh oxygen. In summer, when the water supply dries up, the moderately nutritious silicate rock becomes quite dry. Due to the water resources, the torch lily has its main growth phase in the wet winter and spring in its homeland, while it is dormant in the dry summer phase. In our latitudes, the flowering period shifts to summer.
Now about its appearance: The torch lily is clump-forming. Many of the narrow, long and keeled leaves are therefore close together and form a so-called eyrie. The shoot axes, on which several intensely colored flower candles are enthroned, usually protrude about one meter high from these. The upper flowers are on these 15 to 30 cm long racemose inflorescencesoften red in color and yellow towards the bottom, sometimes they are also white or green. The flowering time of the torch lily is between June and October, depending on the variety, and lasts a very long time, as the flower unfolds from the bottom up.
The herbaceous plants form horizontal rhizomes which enable them to survive. Thus, torch lilies are perennial. Some species are evergreen. For many, however, the plant parts above the ground die off in winter, so the leaves turn brown.
The most beautiful torch lily varieties and species
About 150 Kniphofia species are known. Breeding has also given rise to numerous hybrids and varieties. We will now introduce you to some types and varieties:
- Kniphofia uvaria: Flowers red to yellow, 50 to 120 cm high, original torch lily, from which today's crossed varieties originated. There are also mixtures of varieties of this type, such as the Grandiflora mixture
- Kniphofia uvaria ‘Papaya Popsicle’: Strong salmon-pink flowers, apricot fading, up to 50 cm high
- Kniphofia uvaria 'Ice Queen': White flowers with a height of 100 to 120 cm
- Kniphofia uvaria 'Green Jade': flower white-green gradient, greenish fading white, 100 to 120 cm tall
- Kniphofia Hybrid 'Royal Standard': Yellow-orange-red course of the flower, height from 80 to 100 cm
- Kniphofia Hybrid 'Vanilla': bright yellow flower, 90 to 100 cm high
- Kniphofia uvaria 'Safranvogel': orange-pink flowers, salmon pink to cream-colored, 90 cm height
- Kniphofia Hybrid 'Feuerkerze': red and orange flowers, 60 to 70 cm high
- Kniphofia galpinii ‘St. Gallen': Flowers in orange with a height of 60 to 80 cm. It is more frost hardy than other species
Planting torch lilies: location, accompanying plants and more
In our latitudes, the climatic conditions - as described at the beginning - do not really meet the needs of the Kniphofia. That's why she has to change her rhythm a bitadapt and go with the flow, so to speak. That's why she also spends her resting phase with us in winter instead of in summer - that's quite an impressive adaptation.
The perfect location for torch lilies in the garden is in full sun, protected from the wind on very well drained and loose soil. A deep, well-draining gravel substrate is ideal. If that is too much effort for you, you should at least loosen the existing soil before planting and mix it with a lot of sand. It is also important that the soil is moderately rich in humus and nutrients with a pH value between 6.5 and 8. It should be dry to fresh, but never dry out completely. In the summer it should be watered more. Finally, it is important that sufficient water is available during the main growth phase. If necessary, short dry periods can be coped with, but lead to growth delays. To avoid dehydration, it is appropriate to mulch the area around the plants. Our Plantura organic pine bark, for example, is suitable for this. This consists of 100% renewable raw materials from the EU, promotes a natural look and suppresses weed growth. In addition, the torch lily can be piled up in winter for winter protection.
Torch lilies are best planted in spring, after the ice saints, to avoid damage from late frosts. In autumn it often fails to grow. Once planted, torch lilies still need to be protected from frost, as they are not reliably hardy. Waterlogged soil and cold, unprotected locations are absolutely unsuitable in winter.
In the bed, the torch lily is planted 60 cm apart, so that there is space for two specimens per square metre. The most appealing picture is achieved with one to three, maximum five plants in the bed. The rosette of leaves - that is, where the leaves sprout from the shoot axis closely together - should be close to the ground and parallel to the surface of the earth, but never below the ground level.
Care should also be taken to choose a site that does not require constant digging nearby. The thick, yellow roots of the torch lily grow in bundles, tapering out to the sides and would otherwise be injured.
Overview - preferred location of the torch lily:
- Planting after the Ice Saints
- Full sun, preferably 6 hours a day ormore
- Porous, loose soil
- Moderately rich in humus and nutrients
- Moderately dry to fresh
- Protect against drying out, mulch for it
- Sheltered from the wind on a warm south side
- Avoid digging in the immediate vicinity
From afar, large clusters of Rocket Flowers captivate with their unique look. The perennials really come into their own in company with tall grasses or ornamental foliage perennials. There are no limits to the imagination as long as the location claims are shared. However, torch lilies do not like it next to highly competitive plants such as asters (Aster).
Examples of suitable companion plants:
Grasses: Pampas Grass (Cortaderia selloana), Soft Feather Grass (Stipa tenuissima)
Flowering Plants: Bearded Iris (Iris barbata), Daylilies (Hemerocallis) , Montbretia (Crocosmia), Yucca (Yucca), Allium, Penstemon (Penstemon) , Indian nettle (Monarda didyma), catnip (Nepeta cataria), mullein (Verbascum), lavender ( Lavendula), Perovskia (Perovskia), Dahlia (Dahlia), Globe Thistle (Echinops sp.), Maiden's Eye (Coreopsis), Yarrow (Achillea), Sun Bride (Helenium), Lilies (Lilium), Gypsophila (Gypsophila )
Potted torch lilies:
In terms of low winter hardiness, planting the torch lily in a pot is an advantage over planting in a bed. After all, the pot can be brought quickly into the protective four walls and also warm up quickly in spring. Since the roots of the torch lily only have a very limited space in the pot, the substrate should be rich in nutrients from the start, but also particularly structurally stable. We therefore recommend our Plantura organic compost. It releases more nitrogen over time and also contains a lot of phosphate and potassium oxide, which promote stable growth and decorative flowering. Since the torch lily in the pot in pure soil quickly threatens waterlogging, a sufficient drainage layer must be integrated. It is therefore important to add coarse-grained components such as expanded clay, sand or gravel. A mixing ratio of 60% Plantura organic compost and 40% structural materials is ideal. You should put a layer of mulch on top to keep the torch lily evenly moist in the pothold.
One to two young plants fit into a pot with a capacity of at least 1 liter, and two to three for more than 2 liter. In an even larger container, there is space for more plants. The upper part of the seedling must not be buried in the substrate here either, but must protrude a good 5 cm. The young plants must be separated into 5 liter pots next year, otherwise they will be too small. An adult torch lily needs a large, wide pot with a volume of 20 L.
Proper care of the torch lily
The torch lily is easy to care for, as it rarely needs to be cut. In winter you should untie the tuft of leaves of evergreen species. As with all plants, over-fertilization should be avoided. When watering, the following applies: avoid waterlogging and drying out. Torch lilies have a hard time with the wind, because it sticks their flowers together and lets them dry out.
Pruning torch lily
The torch lily should only be cut back in spring. Buds and old leaves can then be removed to a height of about a hand’s breadth from the ground. In general, when cutting, always use clean and sharp tools to avoid infection.
Fertilizing, watering and Co.
The following is part of the perfect care for the torch lily:
Fertilize the Kniphofia in the bed:
The Kniphofia has a medium fertilizer requirement. We therefore recommend introducing compost or slow-release fertilizer in the spring before flowering. Our Plantura organic flower fertilizer is ideal for this. With its high potassium content, our fertilizer supports sufficient water absorption and transport, which is essential in a sunny location. Furthermore, the plant can strengthen its tissue and thus survive the cold winter better. Potassium is also important for flower development. Nitrogen and phosphorus and trace elements are also contained in appropriate amounts and support the growth of the torch lily.
Fertilize torch lily in the pot:
As a pot culture, the rocket flower needs to be fertilized more often. To do this, the mulch layer must be pushed aside and our Plantura organic flower fertilizer applied and watered underneath. The ration should be refreshed every three months. Please do not try to work the fertilizer into deeper layers of soil with your fingers or a fork. The risk of damaging the roots is just too high.Then sprinkle the mulch over it again. Fertilization takes place from April to October.
The torch lily is not blooming?
- The torch lily is too young: In the first year after planting, it is common for the torch lily not to develop any flowers. Plants grown from seed can take as long as 3 years to flower.
- If an established torch lily does not flower, this can indicate a nutrient deficiency. If phosphorus and potash are not available to the plants in sufficient quantities, no flowers can develop. Appropriate fertilizer application can fix the problem.
- An unsuitable, i.e. too cold, shady or wet, location can also be the reason for a lack of flowering.
Water the Kniphofia:
The torch lily does not tolerate waterlogging, especially not after it has faded. Drying out should also be avoided. However, the substrate can dry slightly between pours. It is best to water the slightly dried soil in the morning or evening.
Transplant torch lily:
Transplants are possible in spring, but are not well tolerated by the torch lily. However, it is occasionally necessary if the location proves unsuitable. Care should be taken to avoid damaging the rhizomes. Transplanting can be used directly for division. Learn more about this below.
How do I care for a torch lily?
- Fertilize bed culture once in April
- Fertilize pot culture every 3 months from April to October
- Water sufficiently, avoid waterlogging and dehydration
- Rather avoid transplanting
- Pruning back old leaves in spring
Is the torch lily hardy?
Torch lilies are conditionally hardy. They are assigned to winter hardiness zone Z7 and can therefore withstand temperatures of a maximum of -17.8 °C. However, some winter protection is needed.
The flower withers towards autumn but remains. It should also not be removed until next spring as it provides some protection over the winter. The foliage should also remain standing and can be loosely tied together. A loose cover with spruce twigs, leaves or fir twigs is also a good protection against frostMoisture accumulates under the cover, otherwise rot is encouraged. Winter hardiness is reduced if nitrogen fertilization is too strong or too late. Care must therefore be taken to stop fertilizing by autumn at the latest.
Potted plants can be overwintered in cool temperatures of 5 to 10 °C in a light to partially shaded spot. They tolerate light night frosts. In our separate article you will also find hardy perennials that will decorate your garden all year round.
Propagation of Kniphofia
To propagate the Kniphofia you can use seeds or divide the rhizome. After successful fertilization, the Kniphofia produces seeds in small green spherical capsules. After a while, the fruits turn brown and open. Then it is time to remove the germinable seeds. They can be used for propagation on the windowsill from February. Torch lily seeds require a period of cold exposure to germinate. In technical jargon one speaks of stratification. Seeds you have collected yourself can be stored in a bag in the refrigerator until spring. The seeds should be stored at an average temperature of 5 °C for six to eight weeks.
The seeds germinate in the sun, so they must not be covered with soil when sowing. At a temperature of at least 15 °C, the seeds of the rocket flower will take off after around two to three weeks. The potting soil must always be kept moist during this time, as the seeds must not dry out under any circumstances. A covered nursery pot can meet these requirements. It is best to keep young rocket flowers in a greenhouse for the first year to protect them from snails. From the second year they can then go outdoors.
Overview - growing torch lily from seeds:
- Requires cold: store 6 to 8 weeks at 5 °C
- Preculture indoors from February or no-till from April
- Light germinator: do not cover with soil
- Keep Soil Moist
- Temperature: 15 °C
- Duration: 2 - 3 weeks
- 1. year in the greenhouse recommended
Another possibility of propagation is the division of the clumps. This can be done in April. For this purpose, the rhizome must first be exposed, the flowering shootsCut away completely and shorten the leaves of the torch lily to about 15 cm. The roots can also be shortened to encourage new growth.
Then it's time to divide the rhizomes that have been freed from the soil. For a pot culture small, about 5 cm wide sections are needed, for the bed planting as large as possible. They should be cut with a sharp and clean knife. It is recommended that each section has several visible "eyes", i.e. drive systems. To disinfect the interfaces, they can be dipped in charcoal powder and covered with a damp cloth so that they do not dry out.
The rhizomes can then be buried in suitable locations in planting holes with some organic fertilizer. Make sure the roots are pointing down and the shoots are pointing up.
Overview - propagate torch lily by division:
- Time: April
- Expose plant
- Shorten leaves and flowering stems
- Remove rhizome from soil
- For pot culture, divide the rhizome into pieces about 5 cm wide
- Separate rhizome into as large parts as possible for bed planting
- Plant rhizome pieces the right way around with some flower fertilizer
Is the torch lily poisonous?
No, the torch lily is not poisonous. It poses no danger to humans or animals, everyone can enjoy the beauty of the magnificent rocket flower without any worries.
We're not the only ones who like the bright blossoms of the torch lily. Insects also love to feed on their nectar. If you want to offer bees and co. an even larger buffet in your garden, you should read our article about bee-friendly perennials.