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A friend was a market-gardener and when he was starting out, an older gardener challenged him to intentionally germinate thistle seed, just one of the usual "garden weed" species.

C. a. is native to a huge area of Europe from low to high altitudes, so at least some seed will take very low temperatures.

I strongly suspect that your C. a. are a sow (outdoors) and forget seed, just make sure the pot(s) are protected from mice, inquisitive birds and the like. If they behave like "weedy" species, they will germinate over years, not just one.

Quote from: janemcgary on December 28, 2023, 01:25:51 PMSaffron keeps better in the freezer. I also keep paprika and poppy seeds there.

Anything fatty, such as poppy seeds, and nuts definitely keep for ages.

I actually buy all the herbs and spices that I regularly use, in small catering packs - it depends on what it is but 100-250g packs, and they are in the freezer. The first time that I bought whole bay leaves, I had no idea how many I was buying and that pack lasted something around 15-20 years and were prefectly OK when I used the last ones.

PAR meters - the problem will be sales volume, I suspect.

The demand for simple lux meters will be trully vast, especially if cheap - many people who own or are responsible for indoor public or work spaces will have need of one at some stage.

Quote from: Bern on December 28, 2023, 11:04:52 AMI think you also posted a link to one and I will take a look at it also. 

Simple lux meter only - very cheap and lots of different cheap ones are available.

Quote from: David Pilling on December 28, 2023, 03:33:29 AMA young woman has revealed a fool-proof way to tell if someone is extremely wealthy simply by looking in their kitchen.

A judge of stupidity as well perhaps. It goes stale like all natural products and a large jar but sparing use.................... Mine (a very few grammes) is kept in the freezer in a foil bag.

Apparently world production is around 300 tonnes per annum, with Iran producing approaching 90% of it. The amount did surprise me - one hell of a lot of paella and/or pilau rice!

There was mention a year or two back, that somewhere in the Saffron Walden area was looking to enter the traditional trade of the district.

Does anyone grow a few pots/different species of Ferraria?

I have one pot of F. crispa (around 6 plants) which looks to have rust, based purely on appearance - slight yellowing and drying-out of the leaves in patches, which slowly spread. Oddly, a second pot of the same species, a few feet away, seems as though it may have early signs. Nothing so far on any of the other 3? 4? species that I have.

I first thought that I may have over-watered, but that looks all but impossible now.

I did spray once, with a copper fungicide, but it didn't appear to make any difference, but I was far from thorough.

Thoughts, anyone?

Quote from: Piotr on December 27, 2023, 06:55:26 AMHow do you know they are not in Africa?

Check around on UK forums, especially the BCSS. People who do receive their orders do not get them posted from Africa. Some items never turn up and identification is not always reliable.

Amaryllid seed is in demand and is ephemeral, so it is in stock with Lifestyle and Silverhill only for short periods - it is out of stock for far longer than it is for sale.

Germination is absolutely not at all a problem - the seed germinates more easily than cress. Getting seed to you alive and viable is the problem. That produces another (financial) problem - ordering small quantities of seed which need a phyto' and international carriage, so that the costs beyond the seed are comparatively large. You cannot wait for 2-3-10 species with ephemeral seeds to become available because they sell quickly and the oldest would probably be dead by the time the last species was available. When there were no restrictions it wasn't a huge problem - just the cost of an airmail letter to receive 10-20 seeds.

There are very few commercial and society seed suppliers in Europe, the USA and RSA that I have not bought from over the past 30 years, or had plants through their seed/bulb X, although a lot of it is now impossible (legally) due to enforcement of phyto-sanitary laws, and due to Brexit. Seed from all of the small number of species of Clivia, Crinum, Brunsvigia, Crossyne and Scadoxus that I have been able to buy fresh, have germinated extremely well, close to 100%, and survival has also been excellent.
I have never bought or sown Gethyllis seed though.

Lifestyle have a reputation, not from me so far, for misidentification - I haven't enough of their seed grown to a size to be able to reliably identify them to be able to comment. They do include collection location and date on their listing though, but you have to check the actual listing for the species - other dates appear elsewhere, such as in search hits.

Quote from: Piotr on December 27, 2023, 04:13:46 AMMaybe somebody who has some will still reach out...

Never say never  

The seed supplier that you mention sounds like this one -  African Yemen Socotra Seeds, Plants – African Seeds (africa-seeds.com)

They appear to be in Namibia, but are actually based in Estonia, or one of the other Baltic states (I can't remember for sure which one). They are also extremely unreliable.

To be legal, you need a phyto' cert' and will pay import duty and VAT when they arrive in the UK. Ideally you also need to pre-register the import with DEFRA.

If you assume that all SA amaryllid seed is ephemeral, you will be close to the truth. A lot actually germinates before it falls from the parent plant, it varies but receiving very fresh seed that has roots is normal so that you really need to order seed only 4-8 weeks after collection. Both Silverhill and Lifestyle will provide this information.
However, I have sown a batch of Crinum asiaticum (not S African) seed and all but one seed germinated within 2-3 weeks, but the last one took 2-3-4 months.
The seeds are ephemeral not because they become non-viable, but because they start to grow so very fast and will die if they have nothing to root into. Strumaria are perhaps the "worst" - I have a couple of plants and the very few seeds that have been set, have all germinated within the seed pod and have had a root a few mm long when I have "harvested" them.
Plants such as Ledebouria and Drimia, and the allied genera, frequently have seed that does "die" if not sown very soon after ripening.

Be very careful if looking at buying cheap PAR meters.
Many, perhaps most or all, are not.

I have trawled Amazon UK and some do not give PAR readings at all, despite what they claim (time and again, these have reviews that state that they do not measure PAR), and some require input of the source - daylight, HPS, LED etc. This being so, the meter is using some kind of "nominal source spectrum" to calculate numbers, in other words it is converting lux to PAR figures by calculation, it is not actually measuring PAR at all.

Quote from: Martin Bohnet on December 26, 2023, 06:31:29 AMI bet other levels of secondary plant substances like aroma, vitamins etc are also affected by "less important" parts of the spectrum

The only major research has been into vegetative growth and flowering - by far and away the most important things commercially.

Although fairly recent investigations suggest that UV affects various chemical components in tomatoes.

In real life, apart from clandestine crops and vertical farming, the vast majority of horticultural lighting is additional to daylight - commercial horticulture on the grand scale could not make money otherwise.

Anyone seriously interested in lighting and plants should take a look on the Philips website - there is an entire (large) library of information available, so much that finding specifically what you are looking for can be quite a challenge.

Apart from SON, they have lots of information on LEDs and metal halide lamps and they also discuss "light recipes", where different blends of colours are preferred, usually in contolling flowering, usually in pot/house plants.

The problem with all meters is calibration, especially where a meter claims to do any kind of wavelength analysis.
I checked the one that I have against one that a friend has (same model), and they gave the same numbers, for what that is worth.

People may find this useful -  Convert Lumens to PPF - Online Calculator | Waveform Lighting

Something that Kelly is obviously not aware of is that the lumen is not one scale - the one used for general lighting is always human photopic (bright light) lumens. If anyone was designing street lighting, they would probably use human eye scotopic (dim light) lumens and for plant growth, anyone would use plant growth lumens.

Somewhere, I have a copy of the GE Excel sheet - Phocalc - you can load spectra into it and it calculates all three types of lumen, plus CRI, colour coordinates etc. etc.. It was used routinely for lamp development.

Quote from: OrchardB on December 25, 2023, 02:42:15 AMIs this just for edible/experimental products or does it apply to other commercial plant propagation?

Photosynthesis is driven by any visible wavelength but is most "sensitive" in the yellow-orange-red, in other words, growth is most efficiently produced by illuminating plants with light in this colour region. This is why HPS/SON/Lucalox (all the same thing) were the normal horticultural lighting prior to LEDs and even today in some circumstances.

Inter-nodal distance ("legginess" of a plant) is controlled by blue light - less blue, more leggy. Not much is needed, but it is essential for normal plant growth.

Other than that, the world is your oyster.

If you read around on the www, sticking to articles led by science and the real world, a lux meter is all that you need, which cost peanuts.

Another couple of easily-proven facts that will probably surprise and/or horrify many -

A greenhouse with spotlessly clean glass transmits around 70% of natural light. This is down to absorption and reflection by the glass and obscuration by framework etc.

Small bubble bubble-wrap insulation absorbs around 15% of natural light.

A modest, barely perceptable, film of algae on glass ,plus bubble-wrap, will cut natural light by over two-thirds. The human eye/brain will see/perceive a difference but not register it as anything even close to that huge.

I have been through this with my own greenhouse, and can confirm that it isn't Philips making numbers up.

LLLOL

Quote from: Bern on December 24, 2023, 07:15:14 AMthe development of sensors that can quantify the photons in the photosynthetically active parts (PAR) of the electromagnetic spectrum and then give you a readout on a PAR meter in µmols per square meter appear to me to be a real advance in understanding

I suspect that it is software, not hardware - FAR cheaper and basically rather simple in terms of both hardware and software; it just means calibrating a silicon photo-cell, although a generic one would be good enough and can be downloaded from the www.