What artificial light would you recommend?

[Vlk]

Hi there!

We have quite dark winters here in Czech republic and I wanted to buy some light for the plants which needs the light most, so I could turn it on from time to time and provide them the light they need. But I am kind of overwhelmed by the variety of different opinions and differents kinds of lights and techniques. Could you please help to determine which light would best suit my need?
I just want a simple light and have a couple of plants under it, let's say 5-6. These would be smaller plants, max. 1,5 years old, all in pots. Mostly, I want to put under light my durian seedlings.
I don't want to buy any hi-end lights, I was just thinking of a simple light bulb, a mere little support during the winter periods :-)


Thank you in advance for any tips and tricks!

[KarenRei]

Hi there!

We have quite dark winters here in Czech republic and I wanted to buy some light for the plants which needs the light most, so I could turn it on from time to time and provide them the light they need. But I am kind of overwhelmed by the variety of different opinions and differents kinds of lights and techniques. Could you please help to determine which light would best suit my need?
I just want a simple light and have a couple of plants under it, let's say 5-6. These would be smaller plants, max. 1,5 years old, all in pots. Mostly, I want to put under light my durian seedlings.
I don't want to buy any hi-end lights, I was just thinking of a simple light bulb, a mere little support during the winter periods :-)


Thank you in advance for any tips and tricks!

If you do the math where you factor in how much you'll be paying for power over the lifespan of the bulbs, you'll find that LEDs almost always win. They have higher capital costs, which probably scare you off, but realize that you'll be paying a lot more for power than you pay for bulbs, so it's not the upfront costs that matter most. Don't step over a dollar to pick up a dime - it's efficiency that matter, and LEDs will get you about twice the growth per watt.

Realize that no matter what you do, it will be relatively expensive. It's all proportional to how much area you want to support and how much you want to support it, but you're trying to impersonate the sun, and the sun is REALLY bright.

Here's the good news: seedlings don't generally need as much light as full grown trees, if you're just trying to keep plants alive then you won't use as much energy as otherwise, and if you're only trying to cover a tiny area for a couple little seedlings, then costs can be kept down.

If you don't go with LEDs:

 * HID (HPS, MH, etc) are fine. Make sure that the bulb does *not* get wet. They run hot and it's dangerous to get them wet - it's even possible for them to explode. They're also high voltage.

 * Fluorescent are also high voltage but they don't run hot and aren't as water sensitive. The thinner the tube, as a general rule, the more efficient they are, though it's not a *huge* difference. HIDs are often more efficient... in the beginning. But their efficiency drops dramatically with time, and you're not going to want to change bulbs all the time, as they're expensive bulbs. Also it's easier to get electronic ballasts for fluorescent than HID, and electronic balasts are more efficient than magnetic, all issues of bulbs aside. They also last longer, help you use older bulbs, and all sorts of other advantages - strongly recommended if you can get them. Note: since the light isn't as intense, they need to be much closer to the plants, or you need to create more of a "light wall". Ideally, if you put your hand where the plants are, you should be able to feel the warmth of the lights, but it shouldn't be hot.

 * CFL are fluoresents with a built-in magnetic balast. Usually not the best buy by the numbers, but they work just fine and can be good for nooks and crannies or creating high intensity areas.

 * NEVER use incandescent or low pressure sodium. Incandescent creates too much heat relative to how much light they make. Either they're close enough that you burn your plants, or they're far enough away that the light they give off doesn't make much of a difference.

Timing: people aren't in agreement on this. I'm a 24/7 proponent. Few people have enough light fixtures to create as much light as the plants would really like. Some plants require darkness for flowering or whatnot. However, most plants really don't care. So long as all of the parts of the plants aren't overloaded in their ability to create or move sugars around - extremely hard to do with supplimental light - more time with lights on simply means more energy for the plant.

Other: is this just about light, or is this your first time as an indoor grower?

[Vlk]

Thanks for your reply!
I would like to use the light as a secondary source. The place where I got my plants is pretty sunny when the weather is all right, but there are months, especially during winter, where days can be pretty dark. I had an idea of this artificial light, which I would occasionaly turn on in these situations to get the plants some light and help them get through these dark times better.
The reason I don't want to go into LEDs is that I don't want to go serious with the artificial lighting. As I said, I just want it as a small secondary source and support for my seedlings.
I found these bulbs http://www.grow4u.cz/shop/detail/12/34/Agrolite-125W-blue-rust#.Ups_ZMQ2beJ which I think could be pretty sufficient for my need. It costs small amount of money and it is power saving.
You got a point with not getting the light bulbs wet - I must admit I haven't think about that. As I want to mist my plants often, I will need to think of some protection for the bulb..

[KarenRei]

Thanks for your reply!
I would like to use the light as a secondary source. The place where I got my plants is pretty sunny when the weather is all right, but there are months, especially during winter, where days can be pretty dark. I had an idea of this artificial light, which I would occasionaly turn on in these situations to get the plants some light and help them get through these dark times better.
The reason I don't want to go into LEDs is that I don't want to go serious with the artificial lighting. As I said, I just want it as a small secondary source and support for my seedlings.
I found these bulbs http://www.grow4u.cz/shop/detail/12/34/Agrolite-125W-blue-rust#.Ups_ZMQ2beJ which I think could be pretty sufficient for my need. It costs small amount of money and it is power saving.
You got a point with not getting the light bulbs wet - I must admit I haven't think about that. As I want to mist my plants often, I will need to think of some protection for the bulb..

Don't buy anything without doing the math on the cost of power over the lifespan of the bulb. Power costs don't care whether you're "serious" or not. If you cant afford the cost of a LED bulb then you can't afford the cost of the power to run your bulbs whatever type they are, in the long run at least.

Do the math.  Or I can do it for you if you give me your cost per kilowatt hour and what various bulb types available to you (type, watts, lifespan, bulb cost, fixture cost) and how many watts of non-LED you were thinking of buying.

There are a number of indoor growers on this forum who live in areas not naturally conducive to tropicals (I live in Iceland, for example). I'm probably the second most extreme, after CoPlantNut, who has a couple times the indoor area and wattage (I only win on height    ).  After growing for years without them, he switched out his entire system to LEDs and ended up so in love with them that he invested in a company that makes them. I use a mix of fluorescent and LED, but now that LED fixtures are increasingly broad spectrum, even here in dirt-cheap-power expensive-import-taxes Iceland they're still a better choice, so I'm slowly shifting over as well.

[Vlk]

Thanks for your reply!
I would like to use the light as a secondary source. The place where I got my plants is pretty sunny when the weather is all right, but there are months, especially during winter, where days can be pretty dark. I had an idea of this artificial light, which I would occasionaly turn on in these situations to get the plants some light and help them get through these dark times better.
The reason I don't want to go into LEDs is that I don't want to go serious with the artificial lighting. As I said, I just want it as a small secondary source and support for my seedlings.
I found these bulbs http://www.grow4u.cz/shop/detail/12/34/Agrolite-125W-blue-rust#.Ups_ZMQ2beJ which I think could be pretty sufficient for my need. It costs small amount of money and it is power saving.
You got a point with not getting the light bulbs wet - I must admit I haven't think about that. As I want to mist my plants often, I will need to think of some protection for the bulb..

*
Don't buy anything without doing the math on the cost of power over the lifespan of the bulb. Power costs don't care whether you're "serious" or not. If you cant afford the cost of a LED bulb then you can't afford the cost of the power to run your bulbs whatever type they are, in the long run at least.

Do the math.  Or I can do it for you if you give me your cost per kilowatt hour and what various bulb types available to you (type, watts, lifespan, bulb cost, fixture cost) and how many watts of non-LED you were thinking of buying.

Well, math, uhm... you mean that thing I have no idea of? :-D

You are very kind to offer me that. Well, I did some research and Kilowatt per hour costs 4,53 Kč per hour, which is 0,23 dollars. I was thinking of buying 125 W power saving bulb I sent link to in my reply. There are not much informations there, only watts and that is has 6500K. I found official page of the company, but not much informations there either. http://www.agrolite.com/ficha.php?idioma=ing&art=cfl
I thought I would get this bulb and get it running for, let's say 2-3 hours max and turn it off. And not every day for all the winter. Just occasionally. I guess that can't be that expensive especially with power saving bulb right?

[KarenRei]

2-3 hours with 125 watts is essentially useless in most circumstances. Just letting you know. And if you're going to suppliment and pay the cost for a fixture, it'd make more sense to run it longer using a less powerful bulb than to run it for so short a period of time.

Okay, let's look at what you'd pay over 50,000 hours of usage. Now, you might do 50,000 hours over 6 years with 24/7 usage, you might do it over 25 years with using it about 20% of the time (partial winter supplimentation)... however you do it, the math works out the same (unless we want to get complicated and factor in interest and inflation and depreciation and the like    ).  And if your response is "I'm not going to use it 24/7 or even 20% of the time", see the above paragraph. I mean, you *could* just point a 5W flashlight at your plants for 5 seconds each day, but that doesn't mean it's a meaningful endeavour    The total amount of light energy has to be sufficient to matter or it's pointless.

Such a bulb probably has a lifespan of about 20k hours. So 5k hours is 2 1/2 bulbs. Fixtures don't last forever either, but let's be generous and say 50k hours. 50k hours is what you'll get out of a single good LED fixture (no separate bulbs). Let's assume the fluorescent fixture costs 600 Kč. So, 700 Kč * 2,5 + 600 Kč = 2.350 Kč

Now for power. 125W for 50000 hours is 6.250.000 watt hours, or 6250 kWh. Times 4,53 Kč is 28.312 Kč. Adding these numbers together, your total costs are 30662 Kč.

Note how vastly more expensive power is than the fixtures and bulbs over their lifespan.

Now, you could get an LED. 125W fluorescent is pessimistically 70W LED or so.  The best Ebay prices of chinese-made LED fixtures are about 1,15 USD per true watt (LED fixtures are often listed in "rated watts" or similar which are double the actual consumption, LEDs are run at about half power to greatly extend the lifespan).  Let's say you pay three times that due to taxes, shipping, more expensive manufacturers, or whatnot - 3,45 USD per true watt, aka 67 Kč.  So 67 Kč times 70W is 4690 Kč.

So yeah, it's a lot more expensive than one bulb. It's even more expensive than 2 1/2 bulbs and one fixture. But what happens when we factor in power? 70W * 50000 hours is 3.500.000 watt hours, or 3.500kWh. Times 4,53 Kč is 15.855 Kč. Plus your fixture cost, that's 20.545 Kč

So let's compare everything side by side:

Fluorescent: 30.662 Kč
LED: 20.545 Kč

But that is of course with pessimistic figures. Let's say you pay only 50% more than the best ebay prices, and you only need 50W LED to compare to that fluorescent bulb.  How does that change the results?

Fluorescent: 30.662 Kč
LED: 13.029 Kč

See the difference? And notice how the real costs are in power?

But let me reiterate, 125W fluorescent for 2-3 hours is virtually meaningless unless the area is tiny. How much area are you talking about illuminating? I can look up online how much sun you'll be getting - are they in full sun all day, or are there any obstructions? I'd like to be able to give you a sense of how much power you'd actually have to run to make a meaningful difference versus just that which comes from the sun.

[Vlk]

Wow man, that's deep! :-) Thanks a lot for your time to take this research. 30662 Kč is seriously pretty scary :-D I imagined buying this bulb, plug it in power and as I said, do so every few hours from time to time. Like the sun which would normally come off for about 2-3 hours in winter and then just dissapears above the clouds.
I would like to illuminate very small area, like let's say, 30x50 cm :-) Having there couple of durian seedlings and not going them grow like crazy, but only making their life more bareable during the winter and to support them little in growth. .-)
If there is sun, they are usually from 12:00 to the evening on full sun (they are on the west side, just behind big window). And so during sunny summer days, I am pretty sure they are nicely covered. But during winter, there can be no sun all day. For example today, there could have been about half an hour, max. hour of direct sun and that was pretty nice exception for this year's winter.
Thank you so much for looking all these things up, I really appreciate it as I am totally new to artificial lighting :-) Thanks!

[Mark in Texas]

Karen gave some excellent advice.

You're buying light.  If you got the bucks and want to keep it simple, it's hard to beat a self contained 250 or 400W HPS in a small horizontal, well designed hood.  Hang it by lightweight dog chains and hooks and adjust the height above the plant canopy as needed.  I guarantee you'll be expanding your faves, trying to kiss all the pretty ladies.    Your garden footprint is very small now but you'll quickly outgrow the lamp you're looking at plus you'll not get much lumen output nor does that lamp have a  highly reflective hood to direct the light where it needs to go - down into the canopy.

Plants need a rest as many important functions occur during lights out.  For veg consider 20/4.  If a photoperiod is important regarding hormonal influences driven by day length regarding a flowering response then you may need to adjust.  Being that your faves are seedlings now and will be in a veg mode for a while..... recommend a total 20/4 photoperiod - natural plus artificial.

Side panel reflectors can increase light that your plants "see" by as much as 30%.  They are extremely important and will help contain humidity within your garden.   Mylar is 93% efficient or my favorite for ease of maintenance, cardboard or styrofoam panels painted with 3 thinned coats of ultra white latex paint is fine.

Good luck!

[KarenRei]

Wow man, that's deep! :-) Thanks a lot for your time to take this research. 30662 Kč is seriously pretty scary :-D I imagined buying this bulb, plug it in power and as I said, do so every few hours from time to time. Like the sun which would normally come off for about 2-3 hours in winter and then just dissapears above the clouds.
I would like to illuminate very small area, like let's say, 30x50 cm :-) Having there couple of durian seedlings and not going them grow like crazy, but only making their life more bareable during the winter and to support them little in growth. .-)
If there is sun, they are usually from 12:00 to the evening on full sun (they are on the west side, just behind big window). And so during sunny summer days, I am pretty sure they are nicely covered. But during winter, there can be no sun all day. For example today, there could have been about half an hour, max. hour of direct sun and that was pretty nice exception for this year's winter.
Thank you so much for looking all these things up, I really appreciate it as I am totally new to artificial lighting :-) Thanks!

Okay, let's see how much light you need to make a practical difference.  This page:

http://www.prague.climatemps.com/january.php

Says you get only 1:46 sunny hours per day in January, mainly due to clouds.  In July:

http://www.prague.climatemps.com/july.php

It's 8:32. So January sunny-hours is only 20% of July, and you want to change this. Right?

Okay, full sun, in-plane, is about 1000W per square meter. But sun is going to be angled. Lets assume no obstructions. Let's say that due to angles you only average 40% of it in summer sunny-hours and 30% in winter sunny-hours.  That means in july, one square meter is getting 3,4kWh per day, and in January, one square meter gets 0,5kWh. You have 0,15 square meters of area - pretty darn small, so that does change things. This changes july to 0,5kWh and january to 0,075kWh from the sun.

Now lets look at your 125W light bulb. Let's say you use it 2,5 hours every other day. 0,125kW * 2,5 / 2 = 0,15kWh. Great, right? Except... no. Because not all of the power that goes into the bulb becomes light. Only about 20% will. If you do nothing to try to contain the light, also, most will not hit your plants, maybe 10-30%. A well designed reflective area that doesn't interfere with the sun may get 60%. Let's go with 60% to be nice. 0,15 * 0,2 * 0,6 = 0,018kWh.

That is to say, *if* you do everything right, you only increase your january light exposure by one quarter. You're providing only 4% of the light difference between summer and winter.  And that's if you have a nice reflector setup.

Is that really what you're trying to do?

Note that reflectors can *also* augment sunlight - just pointing that out.   Also, the best reflector is not mirrored but bright white, it gives you diffuse light which gets better leaf coverage. The cheapest way to get your plants more winter light is just to put some reflective material on their north side. You can also get a bit more light by putting reflective material on the ground in front of them and to their sides.

[Vlk]

Thanks for your reply Mark!

A reflector is a pretty good point - I need to think about that too.

Thanks for all your tips and tricks and for wishing me good luck! :-)

[Vlk]

Wow man, that's deep! :-) Thanks a lot for your time to take this research. 30662 Kč is seriously pretty scary :-D I imagined buying this bulb, plug it in power and as I said, do so every few hours from time to time. Like the sun which would normally come off for about 2-3 hours in winter and then just dissapears above the clouds.
I would like to illuminate very small area, like let's say, 30x50 cm :-) Having there couple of durian seedlings and not going them grow like crazy, but only making their life more bareable during the winter and to support them little in growth. .-)
If there is sun, they are usually from 12:00 to the evening on full sun (they are on the west side, just behind big window). And so during sunny summer days, I am pretty sure they are nicely covered. But during winter, there can be no sun all day. For example today, there could have been about half an hour, max. hour of direct sun and that was pretty nice exception for this year's winter.
Thank you so much for looking all these things up, I really appreciate it as I am totally new to artificial lighting :-) Thanks!

Okay, let's see how much light you need to make a practical difference.  This page:

http://www.prague.climatemps.com/january.php

Says you get only 1:46 sunny hours per day in January, mainly due to clouds.  In July:

http://www.prague.climatemps.com/july.php

It's 8:32. So January sunny-hours is only 20% of July, and you want to change this. Right?

Okay, full sun, in-plane, is about 1000W per square meter. But sun is going to be angled. Lets assume no obstructions. Let's say that due to angles you only average 40% of it in summer sunny-hours and 30% in winter sunny-hours.  That means in july, one square meter is getting 3,4kWh per day, and in January, one square meter gets 0,5kWh. You have 0,15 square meters of area - pretty darn small, so that does change things. This changes july to 0,5kWh and january to 0,075kWh from the sun.

Now lets look at your 125W light bulb. Let's say you use it 2,5 hours every other day. 0,125kW * 2,5 / 2 = 0,15kWh. Great, right? Except... no. Because not all of the power that goes into the bulb becomes light. Only about 20% will. If you do nothing to try to contain the light, also, most will not hit your plants, maybe 10-30%. A well designed reflective area that doesn't interfere with the sun may get 60%. Let's go with 60% to be nice. 0,15 * 0,2 * 0,6 = 0,018kWh.

That is to say, *if* you do everything right, you only increase your january light exposure by one quarter. You're providing only 4% of the light difference between summer and winter.  And that's if you have a nice reflector setup.

Is that really what you're trying to do?

Note that reflectors can *also* augment sunlight - just pointing that out.   Also, the best reflector is not mirrored but bright white, it gives you diffuse light which gets better leaf coverage. The cheapest way to get your plants more winter light is just to put some reflective material on their north side. You can also get a bit more light by putting reflective material on the ground in front of them and to their sides.

So do you think I should beat it? If it is how you say, it doesn't really make any significant difference.. I can then just stick to a small indoor glasshouse I planned to make and a heating pad.. And just hope that light isn't any significant setback in matter of plants growth and thriving.

[DurianisaDrug]

400watt hps is my vote or move to the tropics! Hahaha we will have baby durian fields and durian parties before too long!

[KarenRei]

. I can then just stick to a small indoor glasshouse I planned to make

Are you talking about an outdoor greenhouse? Do you have experience with them? The learning curve can be a bit steep and meanwhile they can be plant-killing money pits (I grow indoors because of my experience with outdoor greenhouses).

[Vlk]

. I can then just stick to a small indoor glasshouse I planned to make

Are you talking about an outdoor greenhouse? Do you have experience with them? The learning curve can be a bit steep and meanwhile they can be plant-killing money pits (I grow indoors because of my experience with outdoor greenhouses).

Nope, Indoor greenhouse :-) A pretty simple and small version for few tropical seedlings :-) I cannot afford outdoor greenhouse as I don't have a my own land to build it there :-)

[simon_grow]

I didn't read everyone else's replies but you should also keep in mind whether or not you need supplemental heat. If you require supplemental heating, the HID will also provide lots of radiant heat and the ballast can be situated so that you can use the heat coming off it. HIDs have penetrating light whereas LED and compact fluorescents do not and the lumens dissipate rapidly as you move away from the light source.

If you use HID lights, you will need a lot of vertical space and the plants must not be to close to the light source. For something simple and not too expensive, you should consider compact fluorescents or T5/8 lighting.
Simon

[Vlk]

400watt hps is my vote or move to the tropics! Hahaha we will have baby durian fields and durian parties before too long!

You know I would love to do that :-) But moving to tropics isn't that easy I guess.. Because if it would, I would already be there, having a land to plant all these durians! :-D

[Vlk]

Anyway, thank you everyone for your advice, but I think I will not go into artificial light just yet. I will try my best with other techniques to keep my plants thriving and maybe if it will be inevitable and I will have space and money for it, I will buy myself LED system light which Karen recommended. Thanks again! .-)