Arum Lily (Arum) – The Complete Guide

The arum lily (Arum) thrives with magnificent foliage and deep red berry clusters in shady locations that other perennials shy away from. Despite their name, however, they are not related to lilies (Lilium).

If the high poison content is not an insurmountable hurdle, the plant provides decorative accents in beds and containers throughout the year.

Planting Arum Lily Correctly

Wherever there is at least a little light and the soil is both moist and rich in nutrients, the arum lily feels at home.

Loosen the soil well and enrich it with compost. The depth of the planting pit should be twice the height of the tuber.

Place it horizontally in the soil with the buds facing upwards and water with soft water.

Care Tips

Due in no small parts to its extreme toxicity, arum is surrounded by a mystical-occult aura. On the other hand, the perennial proves less mysterious in its care.

Well protected with gloves and skin-covering clothing, give the arum plant these gardening attentions:

  • In spring, water the arum lily abundantly and regularly without causing waterlogging.
  • During the summer, water it at a reduced rate, provided that the rains do not fall.
  • Fertilize the arum lily organically every 2 weeks from April to August.
  • Cut off foliage only when it has completely wilted.

Cut off the decorative berry clusters ahead of time if you don’t want the arum lily to seed.

Alternatively, the bright red fruit cluster decorates the winter garden. Cut them off only in late winter at the same time as the leaves.

Give the evergreen arum lily winter protection by protecting it from moisture and intense winter sun with leaves and brushwood.

An arum lily in a tub or balcony box should relocate to frost-free, not too dark winter quarters.

Which Location is Suitable for Arum Lily?

Arum is the ideal plant to green semi-shady to shady locations in your garden.

Settle the arum lily under deciduous trees, and the plant will receive the necessary spring moisture. A place along the bank of the pond is also welcome, as long as there is no waterlogging.

If there is a brief dry spell in the summer under the dense canopy of foliage, a wintergreen arum does not mind this circumstance. You can quickly remedy that on the deciduous arum plant with a sip of water.

The Right Planting Distance for Arum Lily

In order for an arum lily to perfectly fulfill its role as a magnificent foliage ornamental plant, the planting distance should be generous.

Place the plant at a distance of 16 inches (40 cm) from its neighbors. To green a larger area with arum, we recommend an arrangement of 6 specimens per 10 square ft.

What Soil Does the Arum Lily Need?

In order for the arum lily to present its decorative foliage, pretty flower, and spectacular fruit set, the soil should be nutrient-rich, humus-rich, and moist without waterlogging.

If the plant sets its impressive accents in a pot or balcony box, choose a high-quality compost-based container plant soil as a substrate to meet all the requirements of an arum.

As a typical plant of riparian forests, arum favors a slightly acidic to neutral pH.

What is the Best Time to Plant the Arum Lily?

For a tuberous plant, like arum, fall is considered the ideal planting time.

Nevertheless, you are free to put the arum plant in the ground on any other day during the gardening season. As long as it does not freeze, the plant will take root vigorously and quickly.

When is Flowering Time for the Arum Lily?

The flowering season of the wild Arum extends from April to June with rather inconspicuous, greenish-white bracts around the flower bulb.

While the deciduous foliage is already starting to retract in the fall, this species boasts bright red and extremely poisonous berry fruits.

The Italian arum behaves similarly. Its leaves, on the contrary, only sprout in the fall to decorate the garden throughout the winter. This arum plant blooms as early as March with calla-like bracts in subtle white.

Pruning Arum Lily Properly

Cut off the foliage near the ground only when it is completely withered. Until then, the underground bulb extracts the remaining nutrients from the leaves to form reserves for the next season.

Unless you don’t desire self-seeding of the plant, cut the berry stand before it can release its seeds. Admittedly, in this case, you deprive yourself of the winter sight of its colorful ornament with bright red berry clusters.

Perform any pruning work on an arum lily wearing gloves and long-sleeved clothing. Even a slight touch to the plant can cause symptoms of poisoning.

Dispose of any prunings in the household trash or place them in a municipal composting facility.

Watering Arum Lily

Water the arum lily in the bed abundantly and regularly, especially in spring. In the summer, a wintergreen arum plant will tolerate intermittent drought without harm.

On the other hand, you should keep a deciduous plant constantly slightly moist. Ideally, use collected rainwater or pond water alternating with tap water to prevent excess lime from accumulating in the soil.

Fertilizing Arum Lily Properly

Fertilize an arum lily in the bed from April to August every 2 weeks with compost, horn shavings, and nettle manure.

Cultivated in a planter, applying a liquid fertilizer twice a month covers all nutrient requirements. Since the plant does not smell pleasantly anyway, you might even use liquid manure made from nettles, and comfrey leaves as a liquid fertilizer.

Wintering the Arum Lily

In the bed, the cuckoopint (Arum maculatum) does not require any special precautions for wintering. The evergreen arum known as Italian arum (Arum italicum) needs protection from moisture and blazing winter sun with foliage and brushwood.

In the pot and balcony box, the plant preferably relocates to the bright, frost-free winter quarters, so that the root ball does not freeze through.

Propagating the Arum Lily

The easiest way to propagate an arum is by division of the tuber. To do this, dig up a well-established arum in the fall and shake off the soil.

The daughter tubers will be clearly visible, which in turn already have their own buds. Separate these with a sharp, disinfected knife.

Powder the cuts with charcoal powder to seal them. You will then want to plant the mother plant and its offspring in separate planting pits, maintaining the previous planting depth.

Is Arum Lily Poisonous?

As an Arum plant, the perennial is among the most toxic plants Mother Nature has in her quiver.

Streams of highly toxic substances flow through each arum, such as saponins, alkaloids, and oxalate. The hint of touch causes violent skin irritation, even blistering.

Carelessly discarded leaves and other parts of the plant already killed entire herds of grazing livestock.

Since the bright red berries taste sweet and aromatic, numerous children fell victim to the temptation, with sometimes fatal consequences.

Cultivate this poisonous plant only out of reach of children and animals.

All planting and maintenance work should be done with maximum safety precautions. The first duty is to wear long-sleeved clothing, gloves, and eye and respiratory protection.

How Does Pollination Take Place in Arum Lily?

It is a sophisticated strategy by which an arum organizes its pollination.

The flowers emit an unpleasant odor of carrion and urine. Flies and mosquitoes are very keen on this.

They fly to the plant enthusiastically and get caught in an ingenious trap construction inside. The wall of the bag-shaped petal is very thinly wetted with oil so that the insects slip off involuntarily.

They remain trapped in a cauldron until during the night the seed pods burst and pollinate the flies. The next day, the petal goes limp, so the kettle trap releases its temporary captives, equipped with plenty of pollen.

Is the Arum Lily Suitable As a Houseplant?

The large plant family of the Arum family is home to a wealth of magnificent species and varieties that are ideal for cultivation as houseplants.

Well-known representatives are the pretty calla (Calla) or the flamingo flower (Anthurium). Thus, the question is obvious whether the arum lily also has what it takes to put itself in the spotlight on the home windowsill.

It is primarily its tropical congeners that are predestined to become houseplants. The arum known as voodoo lily (Arum guttatum) or the Cretan arum (Arum creticum) have a similar appearance to the popular indoor calla.

How to properly care for arum as a houseplant:

  • A high-quality compost-based container plant soil is a good choice for substrate.
  • A drainage above the water outlet prevents waterlogging.
  • As a houseplant, arum prefers a semi-shaded location at normal room temperatures.
  • During the growth and flowering period, keep the substrate constantly moist and apply liquid fertilizer every 14 days.

If the tuber has completely retracted its foliage at the end of the flowering period, cut it off close to the ground.

By then, you should have already gradually reduced the water supply and completely stopped giving fertilizer. Then take the bulb out of the substrate.

The plant spends the winter dormancy in a dry, cool place at 46-50 °F (8-10 °C). In February, pot the arum bulbs in the fresh substrate and start watering sip by sip.

Beautiful Varieties

  • Cretan arum (Arum creticum): This non-hardy plant captivates with its decoratively folded back white flower. It has a height of growth of 16 inches (40 cm).
  • Italian arum (Arum Italicum): A magnificent species with huge, bright red berry clusters in autumn. Its growth height is up to 32 inches (80 cm).
  • Arum purpureospathum: A rare, Mediterranean arum with purple flower stalk. The growth height is 14-18 inches (35-45 cm).