Winter tomatoes grown under lights...

[~misfit~]

.. will remain just a dream for me it seems.

Once upon a time in another life I grew certain medicinal herbs under artificial light (and subsequently got sent to prison for it). Back then the accepted way was to flood the area with masses of light, even if it wasn't the right spectrum. As long as you supplied enough of it the plants did well. Either High Pressure Sodium lights or Metal Halide, whatever gave you the brightest light per watt.

Flowering was simply a matter of adjusting the timer to shorten the photoperiod and, voila! A week later the plant starts flowering. It was as if I was the plants God, I controlled them completely. I grew in soil mixes of my own crafting as well as experimenting with hydroponics and even had an aeroponic system for propogating cuttings. I was very successful having always been a 'greenfingers'. However the electricity bills were massive (as was the impact of imprisonment on my life and health).

Fast forward a few decades and I'm an invalid on welfare growing what food my pain allows me to (as only the rich - or at least moderately well-off can afford to buy tasty nutritious fresh fruit and vegetables). I've always been an early adopter of technology (when I can afford to) and my home lighting has become all LED, moving on from the CFLs I was using since they first appeared on the market decades ago. The savings in running costs soon cover the outlay if you buy carefully.

I got to thinking; Light can not only be produced for around 10% of the electricity cost it was when I grew under lights but also you can also essentially select exactly what spectrum you want with LEDs. That means that you don't need to emit the ~80% of the spectrum that plants *don't* use so the cost reduces by a further 80%. That means it's possible to provide a plant with all the light that it needs for less than 5% of what it used to cost back in the bad old days.

( and is one of the cheapest ways to produce a good growing spectrum. There are other emmiters and drivers available on that site and others. All you need are basic soldering skills and a heatsink to fix the emmiter to. It doesn't have to be a big one as that driver is under-driving the LED, only giving it half of the amps it is rated for so it's producing far less heat than at rated power.)

I bought a few LED emmiters targetted at plant requirements like the above and have used them over my aquarium with amazing results. Plant growth is rampant - but the spectrum isn't that nice for a decorative aquarium. As I had such bad luck with my tomatoes last summer (I'm in NZ so it's mid-winter here) and I have some emmiters and drivers spare so thought to grow a cherry tomato plant under lghts in a built-in closet in the spare room. I had some seed saved from a couple years ago.

So I used up a good portion of my 'low-pain' time over the last few weeks building a frame to hold the LEDs (I added a couple of 3w white LEDs to fill out the spectrum) that hangs on light chain up to two hooks (easy to adjust the height link-by-link) and germinated some seeds, selecting the best. Now the plant is a couple of feet tall, thick-stemmed and with dark green leaves and producing it's first flower spray, looking good! Except.....

Only now do I read a bit about growing tomatoes under lights (oh the arrogance!) and discover that, to produce fruit they need daytime temperatures above 17? C, ideally closer to 20? C. I mentioned I'm poor? I can't afford to heat my home, LEDs have revolutionised lighting but heat still costs big bucks. (It's 2pm and I'm currently sitting in a 13? C room with lots of layers of clothing, my bedroom was 7? C at 7am yesterday.)

I have a thermometer in the closet with the the plant and daytime temps have been in the very low teens lately with nightime temps dropping to single digits. What little waste heat there is from the LED and power supplies is raising the temps in the closet somewhat above ambient but nothing like the masses of heat that *had* to be dumped from grow areas once upon a time. It seems high-efficiency lighting can be a double-edged sword.

If I can't afford to heat my living space there's no way I can afford to keep my tomato plant cosy and warm - even if it's in a very small space (about 3' by 2' and 6' tall - but uninsulated). However after all the trouble I've gone to I night try to heat the space to ~18? C for four or five hours a day - *if* I can devise a small heat source for the job. (I have a spare thermostat

I just need a ~200w small-footprint heater but for the life of me can't think of something I can re-purpose for the job. It's not as if I can afford to buy anything more for this experiment.

Anyway, maybe a bit off-topic for this forum but I thought I'd share. Wish me luck!

[Mike Spencer]

Consider one of those red/infra-red heat/flood lamps used to keep baby chicks warm. I think they're 150W or 200W. One should heat that small a space well enough that you'd need your thermostat to turn it off occasionally. I suppose if you're way south on South Island and your space has an outside wall below 0C, it might not be enough but if the surrounding walls are somewhere around 5C and up, it should be enough.

You can just put it facing downward in a hanging socket, a foot or more from the plants themselves. You can experiment with surfaces that will absorb the IR and then warm the air by conduction -- black-painted chip board or sheet metal, maybe.

Luck!

[~misfit~]

Hi Mike, thanks for the reply.

I'm really broke so any further expense is out of the question. However I actually thought of something that I have that I can re-purpose that seems to be working. It's my 'heavy-duty' soldering iron that I haven't used for a year or two anyway. It's only 60w but, before I set it up in the closet it was 12C and after an hour it was 15C and two hours later it hit 18C. (That's just opening the door a crack to see the display.) It was around 12C ambient, not as cold today as it has been of late - we had a cold snap. I'm in the North Island, just South of Auckland.

I have a computer fan in there to shake the plant a little bit (promotes strong stem growth and will help pollinate ). I've got the soldering iron wired onto a piece of 4mm thick aluminium sheet, propped up on a little stand thing at floor level. If today's any indication it'll probably run half of the time during the day and I've got it to go off with the lights so for 8 hours it will cool off. If I open the closet the temp can drop 2 or 3C like a stone, in 15 seconds then it takes the little 'heater' half an hour or more to bring it up again. I'll have to keep my nose out of there except for essential stuff or on warmer days.

It would be hard to use one of those heat lamps as the LEDs have pride of place - right above the plant. If I'd used one I'd have had to go the 'absorbent surface' route.

Thanks heaps. I'll report back and let you know if I get fruit and how it goes - if I can afford the on-going electricity. I know it doesn't sound like much but each month that I manage to reduce my debt load - about half of them with it increasing the other half - is a little victory for a lot of going without. That soldering iron just more than doubled the electricity costs of this experiment - and I may need to run more LEDs yet as the plant grows.

We shall see....

[Drew Lawson]

In an interesting intersection of vocabulary, in the late '80s such herbs were often referred to as "tomatoes" in online discussion groups. Allegedly that made it harder for law enforcement to know what they were growing.

[~misfit~]

I remember that - the feeling amongst growers was that picking tomatoes as a psudonym was a good idea because they were a similar sized plant and also an annual so were likely to requre broadly similar environments. I subconsciously used this in thinking I could take what I knew from growing cannabis in controlled condtions and apply it to growing tomatoes.

Boy was I wrong! Cannabis grows vertically in proportion to the amount of light it receives - if you can give it intense light (without 'burning' it) then it stunts its growth, shortens its internodes and produces a very short, bushy compact plant. If you keep the light source the optimal distance above the growing tops of the plant you then get lots of 'plant' in a small space. However I'm finding that these cherry tomatoes on the other hand keep their tall and straggly growing habits regardless of how much light you give them - growing from seed likely didn't help much either as it's almost half a metre from the soil to the first flower bunch.

So I decided to leave the laterals in place and hope for fruit from them. However as I have to keep raising the lights above the top of the plant the lats get much less light and so bolt, with extremely long internodes. I'm having to re-think the whole idea but it's mostly too late for this winter now. However at least I'll be able to start some good cuttings under the main plant so they're ready for an early start outside come spring - hopefully.

My working plan for next year (if I can afford it, the heating cost wasn't something I initially factored into the project) is to grow multiple

*cuttings*, taken and rooted with a proto-flower spray in such a position that it will come to fruition in under a metre vertical space, then take the tops out to prevent the need to raise the lights (and use the growing tip as another cutting). So one flower spray / fruit bunch per plant and multiple plants (cuttings). That way I can use perhaps six smaller pots and cycle plants in and out on (maybe) a 20 day cycle so there's always a fruit bunch (or two) ripening at any one time.

It will mean spacing the LED emitters out horizontally rather than having them in a psuedo-sun layout that I'm currently using. This will complicate cooling of the emmiters as, at the moment I have them all on one large heatsink with a low speed fan cooling them. I'm thinking of modifying a 3 foot aquarium light hood for the purpose, gutting it of the fluorescent ballasts and tubes and retro-fitting the LED emmiters (the closet space I'm using is just under 4 ft wide and 1.5 ft deep). I'm currently using 3 x 10w emmiters above the plants and 4 x 3w above and to the sides. The leaves are a lovely healthy very very dark green and the plant is growing like crazy so perhaps 4 x 10w emmiters spread out horizontally will be good for this space.

I should have used teh intarwebz - I could probably have saved myself having to discover that tomato plants don't auto-stunt in the presence of strong lighting in the way that cannabis does - the info is probably out there somewhere.

Anyway, update as promised - for the edification of readers if wanted. ;)

[~misfit~]

Hi Derald. Yes - I erred on the side of too much light rather than too little, attempting to keep internodes short. Not hard to do with high-power LEDs and a small area. As for wavelength I'm using a 50/50 mix of 8:1 red:blue 'grow spectrum' LEDs (with most output at 450 and 650nm) and cool white "full spectrum". The leaves look amazingly healthy, very dark green, with a hint of purple. The kind of colour you only see when you're giving them the equivalent of more than two times 'full sun' levels of light with a good dollop of near-UVB.

[~misfit~]

Oh well, this experiment was a failure, I turned the 'heater' off yesterday. The fan wasn't enough to 'wind pollinate' and I didn't try hand pollination (perhaps I should have - I've done it successfully on other, larger flowers before). Of the first two flower sprays half of the flowers have dropped off with no fruit forming. There are no bees around outside, bumble or otherwise, I haven't seen one for ages so kidnapping one for a short time isn't on the cards and I don't fancy imprisoning one long-term in autmn next year.

I know that the commercial greenhouse growers bring in captive-raised bumble bee nests for pollination duties. (Apparently for tomatoes bumbles are the way to go as they 'buzz-polinate' as many if not more flowers as they deliberately pollinate. It's all to do with the frequency of their 'buzz' and vibrations on the flower spray causing the flowers to eject pollen.)

Alas, it was largely a waste of money despite the plant growing like crazy and looking extremely healthy. I haven't turned off the lights and as I'm contemplating putting the heater back on and trying to hand-pollinate the last few flowers on the current sprays. I'll 'do my finances' and see if I can afford to keep the heater running another month to try that out. The plant itself will serve as a source of cuttings for putting out early. Going by what I read (and seen) it doesn't need heat for vegetive growth, only for fruiting.

[~misfit~]

So it seems I had half of the answer, knowing about 'buzz pollination' of tomato flowers. A quick Google gave me the other half (now that 10+ flowers have dropped off each of the two sprays). An electric toothbrush seems to be the best way to pollinate tomato flowers - the vibrations cause the pollen to fall onto the style the same way as a bumble bees vibrations do.

Now I just need to find a cheap battery powerd toothbrush. I just tickled the three or four remaining flowers with my Braun Oral-B but it would be nicer to have a dedicated cheaper tool for the job.

[songbird]

~misfit~ wrote: ...

i think just dinging them with your finger can be enough. both simple and inexpensive... :)

songbird

[~misfit~]

Hehee! You're likely right. However I've read that you can get very cheap electric toothbrushes that use an AA cell, I have a lot of good quality rechargeable cells and it's easier on my poor old back to touch them with a toothbrush than to bend down *too* much. ;)

Also the fan I had in there moving the plant didn't pollinate and there's somthing about the vibration of a bumblebee, similar to some toothbrushes, that works very well with tomato flowers.

We shall see. If I can find one at the right price I'll get one. Otherwise I have a few old cell phones in the parts drawer - I'm a tinkerer so might try to make something using the little vibrator motor out of a cell phone, if and when I get the time...

[~misfit~]

A quick 'pop-science' article on buzz pollination;

After a bit of research it seems that there's a range of frequencies that work. Different (non-apis) bees used for tomato pollination produce different frequencies. Here in NZ we have four species of bumble bee and, while I was unable to find their 'sonication' (buzz pollination) frequencies it seems they all manage the job. From what I've been able to find nobody has researched the frequency of whatever native bee evolved alongside the various Solanaceae varities.

I live in the middle of NZs main market garden area (Pukekohe) and there is a company which supplies especially designed cardboard bumble bees nests complete with inhabitants to greenhouses (along with parasitic wasps that prey on aphids and a whole bunch of other beneficial insects). I used to know someone, a friend of a friend, who worked for them but that was a long time ago. This isn't that company - they were commercial only.

However it seems that, in the last few years a few outfits have sprung up doing similar things.

As for electronic solutions there are several on the market - again domestic and commercial units, and again I'm having trouble finding out about commercial units as they all seem to have their websites 'gated' behind customer log-ins. They don't want to be bothered by the hoi polloi. As far as domestic buzz pollination devices go the most common cheap single speed device runs at 38,000 vibrations per minute (38kvpb)which is equal to 633Hz

and their more expensive multi-speed model has five settings from 29kvpm to 44kvpm or 483 to 733Hz. Alas I'm yet to find a NZ supplier.

I would hazard a guess that the single speed 38kvpm model is aimed mainly at tomatoes and the multispeed model can be used more efficiently with other species of plants that require buzz pollination. However other sites visited when researching this suggest that a range of frequencies work (as songbird said, "dinging" them with your finger can work). In the feedback on one of those Amazon pages someone says a $3 kids battery toothbrush works "perfectly" - however an hour ago I stumbled on a scientific site (not bookmarked) that had information on how many times tomato flowers were visited by bees - or tickled with 'wands' - against fruit weight and it's obvious that simply getting fruit isn't the whole picture. There are degrees of success.

My plan to minimise expense and perhaps use what I have - namely a phone vibrator might not be the best as it seems they operate in a range from

130Hz to 180Hz depending on manufacturer with an average of 160Hz. This is quite a bit less than the 633Hz that the single-speed 'wand' uses. However it's quite a bit higher than the 'finger dinging' frequency so might be better than flicking the flowers. However if I could find abovementioned $3 electric toothbrush I'd be happy to try that - after all it's about the same price as a single tasteless off-season supermarket tomato and codging something together using a phone vibrator, power source and 'probe' (taping it all to a pencil) would take a bunch of time that I could use doing other, more urgent things around my home.

It seems that quite a few bees other than bumble bees employ buzz pollination and I'd hazard a guess that some of those native bees do. (After all Florida isn't that far away from where a lot of these plants evolved, certainly on the same continent.) There's no reward for non-buzz polinators at tomato flowers (no nectar and litle accessable pollen) so it's fair to say that if they're visiting the flowers for more than a quick check they're buzz pollinating. To be sure you can always get close and listen. :)

Cheers,

[~misfit~]

Probably because bumble bee nests are short-lived, a season at most. However it's possible to bone up on all things bumble bee and make (or purchase) excelleny nesting sites and encourage (or capture) new young queens and establish new nests.

Also a lot of these commercial 'products' are aimed at greenhouse growers of tomatoes and include a (limited) supply of 'nectar' (often diluted low grade apis honey). While bumble bees can exists mostly on pollen, as in a tomato greenhouse, they also need a quantity of nectar. As tomatoes don't provide it commercially supplied for growers nests incorporate a certain amount, enough to keep the nest viable for six weeks or so, depending on supplier.

The downside of living in a Pacific Paradise is the relatively small consumer base. So far I haven't been able to source an electric pollinator here. Heck, I haven't even been able to find a 'throwaway' battery toothbrush - at least online. The last time I was in the supermarket they had their own brand of rechargable toothbrushes that were cheaper than the Braun brushes on the next shelf but were still >$25.

Being a broke invalid with social anxiety as well as chronic back pain I don't get out much and when I do it's an efficient trip, get what I need and get home. (Also I have a 30 year old car that I maintain myself because I can't afford to pay someone else to do it and I *can* as it doesn't have too much in the way of electronic gizmos. I got it cheaply as it'd been 'cooked', radiator run dry seven years ago and despite driving with a light foot the rattles are starting to get worryingly louder lately.) On top of the anxiety I don't need the temptation of seeing things that I can't really afford. However I must save up a bit of morphine and make an effort to 'shop around' because I *know* I've seen battery toothbrushes somewhere, sometime. ;)

Cheers,

[~misfit~]

[snipped]

Here are a couple of links to sites I found on bumble bees and their life cycle;

I hope the second one is avaiable to you there, it's quite interesting with some video material.

[~misfit~]

Habitat is one of the problems with bumble bees in particular. In most 'developed countries' hedgerow and 'wild areas' are becoming increasingly scarce. Every little bit of land is being used for something, farming is more intensive and houses get closer together.... Then people wonder why there are so few bumble bees (etc.). Honestly, I don't know where they expect them to live. If a nest is discovered it's often destroyed in case someone gets stung.

When I was a lad we were taught to live alongside 'nature', not to annihilate it lest it sting or bite us. I destroy introduced wasp nests if I find them because they do nothing good and a lot of bad. However if I see a bumble bee nest or honey bee swarm I just treat it with the respect that it deserves.

There are no bumble bees in Australia (other than Tasmania) and consequently it's complicated for them to grow certain crops. They're trying to enlist the help of a native bee (blue banded?) that is known to buzz pollinate and are working on how to 'commercialise' it, to get its number s up into 'useful' figures and keep them there in desired locations.

(There's a big anti-bumble lobby who're concerned that certain currently-non-invasive introduced plants would become major problems if an efficient buzz pollinator was present. A bit of a Catch-22 if you ask me as, if they massively increase numbers of the native buzz pollinator then surely that will facilitate the spread of these weeds?)

[~misfit~]

To update this;

The first two flower sprays didn't pollinate despite a fan blowing air around and much finger-flicking. That's when I started reading the internet and so started buzz pollinating with my electric toothbrush daily. Since then I have small fruits forming on all flower sprays. :)

Unfortunately the tall straggly nature of cherry tomato plants means that the plant has outgrown the available space by the third flower spray and, as my budget is so tight I had to turn the heat off after a few weeks of no fruit setting. So in one way it was a failure but in others it was a success.

Lessons learned:

- Tomato plants need a certain amount of heat to fruit (=/>17? C) and LEDs are too efficient to have enough waste heat for the purposes (in my situation).

- Cherry tomato plant retain their tall straggly growing style even in the presence of very intense light and don't 'dwarf' like some other plants do in the same situation. Growing single-spray ~ 3 leaf cuttings and multiple plants would be a better option than a plant from seed for me.

- Buzz pollination is essential for growing tomatoes and in the absence of insects an electric toothbush works very well.

I may try again next winter, growing with cuttings as outlined above and with the LEDs in a 'light bar' arrangement so as to spread the light across several short plants rather than using a (close to) point-source directly above a single plant.

Another good thing to come out of this is that, now that my flowering cherry trees are in full bloom and thick with Tuis and bees and the peach tree buds have swollen and are starting to peek out I have several healthy cherry tomato cuttings ready to go outside very soon (and a source for more). :)

I hope this experiment and the reporting thereof helps others with similar interests.

[Boron Elgar]

snip for brevity only

I am going to give this a try. I have been doing variations on this theme for 40+ years, some successfully, some not....mostly with flowers, orchids and exotic plants, but it is time to try tomatoes.

Right now, I have a "real" plant light set-up, with two bulbs, one for leaf growth, one for flowering. This is all in an upstairs bedroom deserted several years ago by kids who finally fledged, and there is plenty of heat up there.

The only problem with the set up is that I have to be careful about soil enrichment, as I really do not want to introduce insects into bedrooms. So...I will get creative, but won't use any of my delightfully lively compost.

I just got some indigo rose cherry tomato seeds and I might give those a go.

I have played with rambling cherries, and they do quite well wrapped around and over themselves and a couple of stakes. I run 'em in all directions outside...they are so close together with stems overlapped, that it can be tricky to pick the fruit. It is almost like a thick mat of stems.

If I follow through, I will report back. I say this, as currently I have so many tomatoes in the kitchen and the freezer and outside, that I am tempted to take a looooooong tomato break.

Boron

[~misfit~]

A lot of my motivation in setting this up this came from us having 'false start' spring then a cooler wet summer and me losing my outside tomato plants. That and having the LEDs left over from building aquarium fixtures (where I decided that the coloured 'grow-spectrum' LEDs I'd bought detracted from the aquarium visuals too much so I mostly went with white light).

If you do go ahead good luck and it would be great to hear how it goes. :)

[Boron Elgar]

Will do.