Ornithogalum: A Complete Care and Growing Guide for Bulbous Plants

Complete guide to caring for Ornithogalum bulbous plants

Plants of the genus Ornithogalum, popularly known as ornithogalus, star of Bethlehem, hen's milk or white tears, are perennial bulbous plants which stand out both for their ease of cultivation and the beauty of their flowers. Mainly native to Africa, the Mediterranean basin, and Asia, these species have gained popularity in gardens and homes around the world thanks to their adaptation, resistance, and ornamental value. Below, you will find a detailed and updated guide to the Caring for bulbous plants Ornithogalum, covering all species of ornamental interest such as Ornithogalum thyrsoides, Ornithogalum dubium y Ornithogalum arabicum, Among others.

Main characteristics of the genus Ornithogalum

• Botanical family: asparagaceae
• Plant type: Perennial bulbous (in most cases)
• Origin: South Africa, Mediterranean Basin, Asia, some species in South America
• Level: Between 25 and 60 cm depending on the species
• Sheets: Green, linear, fleshy and often striated
• Flowers: Clusters or umbels, striking flowering (white, orange, yellow or greenish colors depending on the species)
• Usage: Rockeries, flower beds, planters, cut flowers and indoor pots
• Flowering time: Mainly late spring or early summer

Main ornamental species of Ornithogalum

The genus has more than one hundred species, of which the most cultivated and commercial are:

• Ornithogalum thyrsoides: Tall stems with clusters of white flowers, very ornamental.
• Ornithogalum dubium: Deep orange or yellow flowers, ideal for pots and small spaces.
• Ornithogalum arabicum: White flowers with a dark center, known as white tears.
• Ornithogalum umbellatum: Small white star-shaped flowers.

Each one has its own particularities, but the care basics are very similar.

Where to plant and locate your Ornithogalum?

These bulbous plants adapt to both gardens like flowerpotsThe most important thing is to ensure:

• A location with a lot of lightThey prefer full sun, although they tolerate semi-shade, especially in very hot climates.
• Environments protected from frost, since the bulb can be damaged if exposed to intense and prolonged cold.
• Well-ventilated spaces, especially if grown in a greenhouse, to prevent the proliferation of fungi.

When and how to plant Ornithogalum bulbs

Planting bulbs depends on the climate in your area:

• En temperate to warm climates, it is ideal to plant in early spring, once the risk of frost has passed.
• If the area is cold, it is best to delay planting until the soil warms up and a sudden drop in temperature is unlikely.
• In mild Mediterranean areas, some gardeners plant in early fall for early flowering in the following season.

1. Prepare the substrate or soil: Make sure it has excellent drainage. In the garden, mix your usual potting mix with coarse sand and/or perlite. For pots, use an aerated potting mix, adding compost and 25% sand.
2. Planting depth: Bulbs are generally buried at a depth twice their size (usually between 5 and 7 cm). Always plant the bulbs with the pointed end facing up.
3. Separation: Leave 10 cm between bulbs to avoid competition between adult plants.
4. Watering after planting: Lightly moisten the substrate to settle the bulb, avoiding waterlogging.

El development until flowering It usually takes 2 to 3 months from the time the bulb is planted, depending on the species and the light and temperature conditions.

Optimal light and temperature conditions

Ornithogalum It requires plenty of light to bloom abundantly. Ideally, it should receive at least 4-6 hours of direct sunlight per day, although partial shade can be useful in climates with extremely hot summers. Indoors, place it next to a bright window.

According to the temperature:

• The general ideal range is between 10°C and 25°C for healthy development.
• Bulbs may be damaged below 5°C. Some tolerate light frosts if the soil remains dry (such as Ornithogalum arabicum).
• In pots, if there is a risk of intense frost, it is advisable to protect the bulbs indoors during the winter.

Proper watering for bulbous plants Ornithogalum

The key to success is in the moderate watering:

• During the growth and flowering phase, water when the soil feels dry to the touch. In spring and summer, watering twice a week may be necessary, always avoiding puddles.
• In its resting period (after flowering and leaf fall), drastically reduces risksIf the bulb remains in the pot or ground, leave it almost dry to prevent rot.
• Drip irrigation is recommended for intensive or greenhouse crops, as it reduces the risk of diseases such as bacterial wilt.

Soil type and fertilizer for Ornithogalum

The ground must be light and well drainedThis prevents the bulb from rotting due to excess moisture. Here are some recommendations:

• In the garden: mix universal soil with one part sand and one part compost or peat.
• In a pot: universal substrate mixed with perlite or silica sand and some worm humus or mature compost.
• Avoid clayey and compact soils.

Subscriber: You can apply specific fertilizer for bulbs or universal fertilizer every 15 days during the flowering stage. In the case of Ornithogalum dubium In professional cultivation, a 2:1:2 NPK mixture or a 7-3-7 liquid fertilizer is recommended, adjusting the doses according to the condition of the plant.

Pruning and management after flowering

Once flowering is complete:

• Cut the withered flower stalks to prevent the plant from wasting energy forming seeds, unless you want to collect them.
• Always leave the leaves until they're completely dry. This is vital for the bulb to accumulate nutritional reserves for the following season.
• At the beginning of dormancy, you can dig up the bulbs (especially in cold areas) and store them dry, in a box with sand and protected from light and moisture. If the climate is mild, they can remain in the ground.

Most common diseases, pests and problems

Ornithogalum rarely suffers from pest attacks, but the following may appear:

• fungal diseases: Excess water and lack of ventilation can cause fungi, especially Phytium and bacterial wilt (erwinia).
• Bulb rot: It is essential to discard affected bulbs and improve drainage before planting again.
• In crops grown under plastic or in greenhouses, ventilate properly and spray preventively against fungi.
• As for insect pests, they are rarely detected in domestic conditions, but it is advisable to monitor for the appearance of mites or aphids.

If you notice any signs of rot, rinse healthy bulbs with water, let them dry completely, and replant in renewed, aerated soil.

Reproduction and multiplication of Ornithogalum

The most common method is the division of bulbs:

• When the bulb enters dormancy and the aerial part dries, dig up the mother bulb.
• Carefully separate and clean the small bulbs or offshoots. These may take one or two years to flower.

• Propagation is also possible by seed, although it is a slower and less common process in home gardening. Seeds are collected from the dried capsules after flowering and sown in spring in fine, moist soil.

Additional care according to each species

• Ornithogalum arabicum: It prefers sandy soils and tolerates light frosts if the bulb is dry. Repotting is recommended if the pot becomes too small and it doesn't need fertilizer, although it responds well to rich soils.
• Ornithogalum thyrsoides: Ideal for cut flowers due to the long lifespan of its flowers in a vase. The bulb can be left in the ground in mild climates.
• Ornithogalum dubium: It excels in pots, accepts light shade to prolong flowering, and requires plenty of light to maintain the intensity of its orange color.

Advanced tips for professional pot and garden growing

• In 12cm pots, use up to 35 pots per m². In 10cm pots, use up to 55 per m².
• To stimulate early flowering in a greenhouse, the daylight can be artificially extended to 16 hours with light of at least 8000 Lux per square meter.
• During germination and early stages, the use of 40% shade netting improves development in warm areas.
• The pH of irrigation water should be around 6 to prevent diseases.
• In low light conditions, applying growth regulators such as paclobutrazol keeps plants more compact.
• During post-harvest, plants can be stored cold (2°C) for up to 2 weeks before sale, without harming future flowering.

Compatibility, ornamental uses and safety

Ornithogalum bulbous plants are excellent for:

• Rockeries and borders in Mediterranean or xeric gardens.
• Medium or large pots in patios, terraces and balconies.
• Cut flower: Flower spikes last for several weeks in water.

They are compatible with other bulbs such as irises, freesias, anemones or ranunculus, creating colorful and long-flowering arrangements.

Most species are mildly toxic if ingested large quantities of bulbs or leaves, so it's best to keep them out of reach of curious pets and small children. However, routine handling doesn't pose any safety issues.