This species is native but not that common. It is also known as Bath Asparagus and that gives you a clue as to where it grows in Britain. There is another species simply known as Star of Bethlehem and that is more common and also it is native but there are many garden escapes. The native form of the ordinary Star of Bethlehem is sub species is O.umbellatum ssp. campestre and the garden plant is O. umbellatum ssp.umbellatum. They are not that different, the garden subspecies has slightly larger flowers.I photographed it recently in Guilford, beside the river Wey which runs through the city. The photograph is reproduced at the bottom of this page.
The Star of Bethlehem is more a plant of grassy open places whereas I have only seen the Spiked Star of Bethlehem growing in shady woodland habitats. Also I have only seen it growing in France and Spain. In Britain it is quite rare and only found in a few places, just 33 of the 10Km squares designated by the BSBI. It is particularly found around Bath and then a few locations east of there also there is a little hot spot in Bedfordshire. In France it is very common, when you drive along the country roads of the Poitou-Charentes area, which is now called Nouvelle Aquitaine thanks to President Hollande. I see lots of it. It will only grow in areas where there is quite a lot of shade. If there is woodland on both sides of the road then it will almost certainly be present, if the woodland is just on one side then maybe it will grow on that side but even then it will depend on the orientation of the road, too much light and it will not be there.
When driving along it is quite distracting because I normally have half an eye out for any interesting wild flowers, much to the annoyance of my wife who would prefer that I gave full attention to the road. I have never driven into the hedge yet but she seems to think it is a possibility. Anyway the flowers of Spiked Star of Bethlehem, especially when they are just coming into bloom look like an interesting Orchid, maybe a Helleborine, Man Orchid or Greater Butterfly Orchid.
Before they come into bloom they also do look like a rather thin spike of Asparagus and you can see why it was called Bath Asparagus. Evidently it was gathered and then sold in markets in Bath for consumption. It still seems to be used in some countries on the Continent, I have also read that there are suspicions that it may be slightly poisonous. Certainly there seems to be some consensus that the bulbs may contain poison and juice from the bulbs can cause skin inflammation. Eating the young flower shoots will probably do no harm if you don’t make them a regular part of your diet, but as this is such a rare plant in the UK then collecting it here is not a good idea and probably illegal.
I found this reference to it in a web site called Plant Lore
‘In the early 1970s Bath asparagus was sold in season in a greengrocer’s at The Balustrade, London Road, Bath. The couple that ran it were at least in their 60s and lived in a Wiltshire village (I think Atworth) near a wood where Bath asparagus grew as profusely as bluebells. I actually bought a bunch once to try it out. They eventually sold the shop and I have not seen it elsewhere since. It is conceivable it sometimes makes an appearance in one of the west Wiltshire street markets, but I doubt it because stalls are usually held by commercial growers’
Below is a photo of the other Star of Bethlehem, the one I found in Guildford and this is supposed to be quite poisonous.