Ornithogalum Dubium - Star of Bethlehem/Sun-Stars

Ornithogalum dubium



Contents

  1. Top Tips
  2. Location, Water, Humidity & Fertilisation
  3. Dormancy Period & Annual Flowers
  4. Common Issues
  5. Origins, Temperature, Propagation, Repotting & Toxicity.


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Top Tips & Info

  • Care Difficulty - Moderate
  • Situate your specimen in a bright location with a minimal amount of direct sunlight. Those kept in deep shade are considerably more likely to develop shortened flowering times and even basal collapse.
  • Allow the top third to dry out in between waters during the flowering process. Reduce this slightly in the autumn and winter to reinforce its dormancy, which in turn could entice a new show of blooms in the following summer.
  • Fertilise once every two to four weeks using a 'Houseplant' labelled feed, depending on the season; fertilise soil will help prolong the flowers' lifespan.
  • Keep an eye out for basal collapse, which is caused by over-watering and possibly too little light. Scroll down to 'Common Issues' for more information on this.
  • Keep an eye out for Mealybugs and Spider Mites that'll inhabit the cubbyholes of its foliage.
  • If your specimen is beginning to lose its leaves over the late summer onwards, don't be alarmed. Star of Bethlehems will go through a state of dormancy whereby most of the foliage will die back until the following spring. Scroll down to 'Dormancy Care & Annual Flowers' to learn more about this crucial period of its life!




Location & Light - 🔸🔸🔸

An hour or two of direct sunlight is best for quality growth. Never situate your Star of Bethlehem in a dark setting as the chance of bacterial diseases, like basal collapse, are far too likely for such a beautiful specimen. The frequency of irrigations solely rely on the amount of sunlight received each day; those situated in slightly darker locations must be far less than with those in strong light. We'd recommend situating yours in a north, north-east or north-west facing window, or in a semi-shaded conservatory or porch for best results. 


Water - 🔸🔸

Allow the top third of the soil to dry out in between waters, reducing this further in the autumn and winter. In some cases, your Star of Bethlehem may lose its foliage from late autumn onwards, which is normal behaviour for specimens at that time of year. Scroll down to 'Dormancy Care & Annual Flowers' for more information on what to do. Under-watering symptoms include a weakened stem accompanied by a loss of flowers, stunted growth and the greying or yellowing of leaves - these issues are commonly down to forgetfulness or too much heat or sunlight. Over-watering symptoms include yellowing of leaves, wilting, basal collapse, and plant death; these issues are commonly due to an area that's too dark, excess moisture in the soil, a too water-retentive compost or water-logging. Scroll down to 'Common Issues' for more information on how to address this problem. 


Humidity - 🔸

Average room humidity is more than enough to occupy a Star of Bethlehem, as too high humidity and poor air circulation will result in powdery mildew. Do not mist the flowers as this will cause botrytis petal blight that can spread quickly if not dealt with accordingly.


Fertilisation - 🔸🔸

Use a fertiliser high in potassium to prolong its flowers during the festive period, at fortnightly intervals - an excellent example would be a Tomato Feed. Regular fertilisers, for instance, BabyBio or Miracle-Gro, will still do the job but will favour foliar growth instead. For the rest of the year, a 'Houseplant' fertiliser can be used to supplement the plant, at monthly intervals.



Star of Bethlehems can produce one or two flower spikes during the springtime, lasting several days once opened. Scroll down to the following section to learn more about achieving annual blooms.



Dormancy Care & Annual Flowers

Shortly after flowering, its foliage will begin to yellow and die off in the late summer. Prune the foliage back an inch above the soil line using a clean pair of scissors or secateurs once all of the foliage has fully yellowed. Place the potted bulb in a dark location that provides low humidity and temperatures around 10°C  (50°F)  for a couple of months. Water sparingly so that the bulb is just 'ticking over' but keep in mind that too much soil moisture will cause root or pythium rot. Once foliage starts to re-emerge in spring, weakly fertilise the plant using a 'Cacti & Succulent' labelled feed and increase the number of waters per week. Relocate the specimen in a bright location with little to no direct sunlight so that it can acclimate to the new surrounding. Keep the soil moist, allowing the top third to dry in between waters and remember to keep an eye for the flower buds that'll develop at the top of the new bulbous growths.




Basal rot is a common issue with recently-purchased specimens, especially after its final flower elapses. Scroll down to the following section to learn more about this phenomenon. 



Common Issues with Star of Bethlehems

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Root or bulb rot is a common issue among specimens sat in too dark environments with prolonged soil moisture. Symptoms include rapidly yellowing leaves, mouldy soil, stunted growth and a rotten collapsed base. Take the plant out of the pot and inspect health below the compost line. If the roots sport a yellow tinge, you're good to go, but those that are brown and mushy must be addressed immediately. In most cases, this will spell the end of its life and therefore must be discarded; this is a normal phenomenon for recently-flowered Ornithogalums, so don't be too disheartened. 

If your Star of Bethlehem develops basal collapse, it will spell the end of its life. The bulb, which is located below the soil line and acts like a modified stem, is the lifeline for a successful specimen, so any issues of rot will kill it outright. If yours has problems of this, be sure to take the plant out of the pot and inspect its roots. Prune away any rotten areas and check its base for a softened profile. Remove any individual plants that have a rotten bottom and repot the healthy specimens in a fresh batch of 'Cactus & Succulent' compost. Provide a brighter location and reduce the number of waters slightly to avoid further rot. Discard the plant if there is no sign of health below the soil line. 

Curling leaves with crispy brown edges symbolise under-watering and possibly too much sunlight. As this species tends to have extensive root systems, you may want to consider a transplant to reduce the number of waters with moister, fresh soil. Scroll down to 'Repotting' for more information.

Due to the species' sensitivity to chemicals, Leaf Shine shouldn't be used to improve the appearance of the foliage, and instead should be cleaned via a rinse of lukewarm water. Failure to do so may cause yellowed, mottled spots that cannot be undone.

A lack of flowers is caused by an insufficient dormancy period, where the temperatures are kept more or less the same over the year. Reduce the temperature by a couple of degrees over the autumn and winter months, along with fewer irrigations to ensure a well-spent dormancy. As spring arrives, the natural temperature will begin to increase, with this is being the perfect time to increase waters and fertilisation. Remember, the warmer the summer days are, the more likely a specimen is to reflower.




Origins

Martinus Houttuyn first described the species back in 1780, using the Latin word for 'dubious', referring to the unusual appearance of others in the genus. The genus, Ornithogalum, was first penned by Carl Linnaeus in the 1750s, using the Latin words for 'bird's milk' that refer to the ivory white flowers of many species. In 2011, the Spanish trio of Martínez-Azorín, Crespo & Juan reclassified the species as 'Eliokarmos dubius'; however, it was declined by multiple horticultural bodies in the U.K., including many of their other reclassification attempts, too.


The Distribution of Ornithogalum dubium.


Temperature

12° - 24°C  (54° - 75°F).
H1b (Hardiness Zone 12) - Can be grown outdoors during the summer in a sheltered location with temperatures above 12℃  (54℉),  but is fine to remain indoors, too. If you decide to bring this plant outdoors, don't allow it to endure any direct sunlight as it may result in sun-scorch and dehydration. Regularly keep an eye out for pests, especially when re-introducing it back indoors.


Spread

Up to 0.4m in height and 0.3m in width once they reach maturity. The ultimate height will take between 5 - 8 years to achieve.


Pruning & Maintenance

Remove yellow or dying leaves, and plant debris to encourage better-growing conditions. While pruning, always use clean utensils or shears to reduce the chance of bacterial and fungal diseases. Never cut through yellowed tissue as this may cause further damage in the likes of diseases or bacterial infections. Remember to make clean incisions as too-damaged wounds may shock the plant, causing weakened growth and a decline in health.

As mentioned in 'Dormancy Care & Annual Flowers', pruning your specimen back to an inch above the soil line is critical for its success in the following year. Remember always to use a clean pair of scissors and locate it in a bright, cool location with good air circulation.


Propagation

Via Seed & Basal Offset Division.

Offset Division (Pups) (Easy) - Separating the bulbed offsets into their own pot will not only expand your plant collection, but it'll also slow the process of becoming pot bound. The best time to divide is during the start of spring, with the pup's bulb surpass 5cm in diameter. Gently brush away some of the soil to gain better access to the bulb's base, where its roots will be housed. While using a clean pair of secateurs or scissors, cut the cord with at least two root strands attached to its base. Set the bulb halfway into a 'Cactus' labelled potting mix and the appropriate-sized pot. The ideal location would provide bright, indirect light and temperatures around 15℃  (59℉) to ease it out of its resting period. Maintain relatively moist soil, allowing the top third to dry out in between hydrations. After the first leaf matures, you'll be able to treat it like a matured specimen by using the care tips above!


Flowers

Star of Bethlehems will bloom in the spring and summer, producing musky orange flowers above its strap-like foliage. The individual flowers will last for around a week, with the overall show spanning several weeks. A second, smaller flower spike will develop shortly after the demise of the previous, lasting a few days less than its larger counterpart. 

Once your specimen finished flowering, the likelihood is that it'll begin shedding its leaves for dormancy. Scroll up to 'Dormancy Care & Annual Flowers' to learn more about this critical period. 


Repotting

For the first two or three years, you won't need to repot the plant as pot-bound roots are more likely to stimulate a show of blooms. After the second year's dormancy period (end of the second year's winter), repot the specimen in the next-sized pot with adequate drainage, using a 'Cactus & Succulent' potting-mix.

Step-by-Step Guide on Repotting

  1. With the new, slightly larger plastic pot with drainage holes, fill the pot's bottom 3cm (1.5 inches) with the 'Cactus' potting mix, before resting the plant's rootball in the middle. Remember not to remove soil from the roots or over-touch this area as Transplant Shock may kill your specimen in some cases. 
  2. Continue to pour soil in the gap between the pot and plant, until the soil line reaches 3/4 of the pot's height. Adding too much soil may result in water runoff when you next come to water it. Do not submerge the bulb under the soil line and instead allow the 'neck' and tip to stay above the. compost.
  3. Similarly to potting a newly-purchased bulb, never compact the soil down for stability, and instead tap the pot's sides a few times for consolidation.
  4. Finally, water the soil well until the small droplets emerge from the drainage holes. If the potting mix becomes uneven, sprinkle some fresh compost into the mounts.


Book a 1-to-1 video call with Joe Bagley if you'd like a personal guide to repotting your houseplant. This will include recommending the right branded-compost and pot size, followed by a live video call whilst you transplant the specimen for step-by-step guidance and answer any further questions!


Pests & Diseases

Keep an eye out for mealybugs, spider mites, fungus gnats, slugs, snails & root mealybugs that'll locate themselves in the cubbyholes and undersides of the leaves, with the exception of the latter in soil. Common diseases associated with Stars of Bethlehems are root rot, leaf-spot disease, botrytis, rust, pythium rot, powdery mildew & southern blight - click here to learn more about these issues.


Toxicity

This plant is classified as poisonous, so if small sections are eaten, vomiting, nausea, and a loss of appetite may occur. Consumption of large quantities must be dealt with quickly; acquire medical assistance for further information.


Retail Locations

Online Stores. 



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