I'm Failing at Indoor Growing.

[Stitchingmom]

I have always started my seeds and put them in a small heated greenhouse so they would get sunlight. This has always worked spectacularly for me, but I am doing indoor growing for the first time andI am on my second set of seedlings, already. I think I might have to trash these like I trashed the first set. The first set I know I stunted because the light was too close, but I don't know what is wrong this time. I am using this light: FAMURS Dimmable TF4000 LED Grow Lights with Samsung LM301B Diodes Includes IR Full Spectrum, hung 24" above the seedlings in a grow tent. The temp is being held between 70-75 at all times, with light for 16 hours a day. I have tomatoes and cucumbers planted. They don't look as bad as the first set, but they just aren't growing again.

I just can't decide how high the light intensity should be right now. I had it about half power but a single cucumber started looking spindly, so I turned it up. I REALLY don't want to have to plant again, because I have never collected my own seeds yet, so I don't have a lot to spare of most varieties.

Any ideas?

Thanks!

[Moth1992]

I have no idea about indoor gardening so this is just brainstorming questions:

Your first set, did they burn? How do you know it was too much light?

You say they look bad? What do you mean? Do you have photos?

[Stitchingmom]

Mostly they are just not growing. Some of the cucumbers sprouted true leaves and just stopped growing. I'll try to get pictures in the morning.

[Lemonboy]

First make sure there are no drafts that might chill the plants or any direct airflow from a heating vent that might dry them out. If you're covering your flats with domes or plastic wrap, take the covering off and tap it on a flat surface to remove excess condensation daily. Mist as necessary to raise the humidity around the seedlings without soaking the soil. You'll still need to water regularly too. No point in keeping the surface moist if you let the rest of the soil (and the roots) dry out.

If the flats aren't covered, lightly mist several times a day to maintain humidity and use a small fan so you get some air circulation around the plants. It helps avoid fungal disease and, weird as it sounds, the "exercise" from being blown around makes your plants stronger. I'd also recommend rotating the flats. Turn them 180 degrees in place in the evening on odd days and shuffle them around on even days. That way if you have a bad spot it affects them all equally but less often and it gives them some variation in their growing conditions like growing outside will.

I wouldn't recommend a heatmat unless you're starting peppers.

Indoor lights put out less lights as they age. They're fine for the first couple years, but start to drop off. It's not a noticeable change to you eyes, but it can be to your seedlings. If you buy used lights or have had yours a while you might want to check them with a light meter. You might also use a thermometer to make sure that at 2 feet your lights don't raise the ambient temperature of your flats. If they're adding heat they're still too close.

I'd guess your problems are mostly temp and humidity. Humidity because you don't keep your house as humid as a greenhouse and temperature because the house has less temperature variation. The grow tent can help with humidity, but use a hydrometer to check how humid the air in your tent is. The seedlings benefit from a change between daytime and night temperatures. Tropical plants don't need that because it's not typical of where they grow. Your tomatoes and cucumbers use a slight temperature change as a signal to either rest or to start a new day's growth cycle. If you're just heating your grow tent with ambient air you might not get that unless you have a programmable thermostat.

Light's a bit trickier. You're giving them 16 hours because they're probably getting less light indoors than they would outside. But depending on how bright your lights are that could be almost twice what they actually need. I'm assuming they're on a bench with no natural light available. Perhaps in a bedroom or the basement? Let us know.

If they'll be in the flats for a while put potting soil in the bottom of the cells and top it with a seed starter mix. If you'll be potting up before planting out just seed starter might give better root growth.

Think about when your seed germinate best. You're trying to emulate late April or early May for them. Think abut what it's like in your area a few weeks before you set out plants in a good year and see how well you're replicating those conditions. And how you can correct for any deficiencies.

[rossomendblot]

The hanging height is fine but I suspect the plants are getting too much light. I have a 100W LED grow light and only really use it at 1/4 power for seedlings, to cover a 2x3 foot grow tent. That light you have can cover 4x6 feet, four times the area of my tent, so if it's a 400W light I think turning it down to 100W would be good enough for seedlings in that space.

There are phone apps which you can use to see how much light your plants are getting, then you can put those numbers in to a lighting calculator to see if the DLI (daily light interval) is too high.

[Toomanymatoes]

If you have close-up pictures of the seedlings, that should help with determining the problem. What is your planting media? It could be damping off or something unrelated to your light.

[GoDawgs]

I use plain old T-8 florescent lights and keep them about 2" over the seedlings and they do just fine. I also use two different tubes in the fixtures, one "daylight" 6500k and the other "warm white" 3000k, supposedly to provider a wider spectrum range. Works great. No heat mat but I do cover the six packs with plastic wrap until the seeds pop and then it's taken off. They seem to like whatever humidity is in the house.

Got any photos of your plants?

[AKgardener]

I had the same thing happen never grew inside unless I was getting ready for spring!! I have many different lights I move my stuff around and keep a fan going I have a temperature and humidity reader but not shure if it’s correct!! My tomatoes are thriving and just saw beginning flowers on 2 of my bell I’ve peppers, I’ve had to redo onions and redoing carrots because there not thriving I think because there staying wet !! I just started cucumbers so lll see how That goes ! I watch and re watch videos haha to see Whst I’m doing wrong how I can do better !! Just keep trying you will get it !! It’s definitely a challenge for me I have to vents in That room and can’t get away from it so I just put something over the rack so it stays warm but it not directly on the plant again trial and error

[slugworth]

maybe too wet

[Stitchingmom]

I will be starting over, but family is coming on Tuesday for Christmas, so I will be doing it after that. Got a light reading app on my phone and ready to go! Thanks everyone!

[MissS]

I have a feeling that your lights are too strong.

[JayneR13]

Yes, photos would really help as well as knowing your grow zone and how old the plants are when they stop growing. I'm growing tomatoes in 5B under a simple T5 light and I do use a heat mat. My lights are close to the plants, perhaps 1' away, and they seem to be growing well. I have had problems in the past with my media producing diseased runts. It could be that your plants are growing their root system underground and not growing many new leaves just yet. As long as there's green, there's hope.

[MissS]

Yes, photos would really help as well as knowing your grow zone and how old the plants are when they stop growing. I'm growing tomatoes in 5B under a simple T5 light and I do use a heat mat. My lights are close to the plants, perhaps 1' away, and they seem to be growing well. I have had problems in the past with my media producing diseased runts. It could be that your plants are growing their root system underground and not growing many new leaves just yet. As long as there's green, there's hope.

She is growing under an extremely powerful light so that makes her situation very different than what that you are using. I think that her plants are overwhelmed by the light more than anything else. This is a classic compliant of the lights being too intense for the seedlings.

[JayneR13]

Yes, photos would really help as well as knowing your grow zone and how old the plants are when they stop growing. I'm growing tomatoes in 5B under a simple T5 light and I do use a heat mat. My lights are close to the plants, perhaps 1' away, and they seem to be growing well. I have had problems in the past with my media producing diseased runts. It could be that your plants are growing their root system underground and not growing many new leaves just yet. As long as there's green, there's hope.

She is growing under an extremely powerful light so that makes her situation very different than what that you are using. I think that her plants are overwhelmed by the light more than anything else. This is a classic compliant of the lights being too intense for the seedlings.

Interesting. This is the first I've ever heard of that. I realize that nutrients plateau at a certain point so more is not necessarily better. I never knew that light was the same way. Some plants really like the extremely bright light, carnivores for example. Garden and learn, right?

[bower]

I wouldn't throw out healthy plants with true leaves just if they were slow to grow. As long as they're not croaking, I would try tweaking your lights one way or another until you find what works. Patience and experimenting.
Your light sounds very powerful and fancy, but I have yet to confirm any LED that really replaces natural light spectrum effectively. Tomatoes are especially sensitive to that, and they need some light from both ends of the spectrum, that is UV as well as IR. Maybe cukes have similar issues IDK. But tomatoes that don't get a suitable spectrum will end up with blistered leaves and stems from edema. The seedlings are way more sensitive to light spectrum than they are to temperature, although for sure they grow faster at 70 F and above. As I understand it, the IR far red and warm end of the spectrum is important for blooms and fruit, but seedlings just don't do well without some UV. My seedlings definitely do best with the light set up over a windowsill, so they can get a few natural rays. Even though it's colder.

Another possibility that occurs to me, and which I noticed this past summer because our relative humidity was so high. Blazing sun and high humidity really arrested plant growth. At a certain temperature they shut down their transpiration to keep from drying out. Ironically not using the water they were getting, so losses were due to direct evaporation from the soil instead.
In order for transpiration to function, there has to be a difference in water pressure from the plant to its environment. If transpiration shuts down, so does growth. So if your tent is really warm and humid and you find the soil is not drying out and the plants are not growing, that could be another cause.

[Stitchingmom]

I went nuts and bought an Aerogarden 24XL. LOL

I'm going to grow in the Aerogarden in the house, due to the frigid temps. I will start my seedlings in the grow tent in February or so. Not giving up, just putting off for a bit. I'm going to do a lot of research on the lights in the meantime. Thanks for all the advice!

[Shule]

I have always started my seeds and put them in a small heated greenhouse so they would get sunlight. This has always worked spectacularly for me, but I am doing indoor growing for the first time andI am on my second set of seedlings, already. I think I might have to trash these like I trashed the first set. The first set I know I stunted because the light was too close, but I don't know what is wrong this time. I am using this light: FAMURS Dimmable TF4000 LED Grow Lights with Samsung LM301B Diodes Includes IR Full Spectrum, hung 24" above the seedlings in a grow tent. The temp is being held between 70-75 at all times, with light for 16 hours a day. I have tomatoes and cucumbers planted. They don't look as bad as the first set, but they just aren't growing again.

I just can't decide how high the light intensity should be right now. I had it about half power but a single cucumber started looking spindly, so I turned it up. I REALLY don't want to have to plant again, because I have never collected my own seeds yet, so I don't have a lot to spare of most varieties.

Any ideas?

Thanks!

An image for the product page says for seedlings to have the height at 20 to 24 inches, and the brightness at 50 to 75%; 18 hours on; 6 hours off. For non-seedlings, for vegetative growth, it says to turn the brightness up to 75 to 100% (16 to 20 inches; 18 hours on; 6 off). For flowering, it says 100% (12 to 16 inches; 12 hours on; 12 hours off). It has pictures of tomato plants by these instructions.

So, if the instructions are correct, then you need to have the lights on a couple hours longer, and you can turn it up to 75%. It doesn't sound like these lights are the super high powered ones that a lot of people have, lately (I could be wrong). How bright does it look? Does it hurt your eyes to be in the same room?

[JayneR13]

I went nuts and bought an Aerogarden 24XL. LOL

I'm going to grow in the Aerogarden in the house, due to the frigid temps. I will start my seedlings in the grow tent in February or so. Not giving up, just putting off for a bit. I'm going to do a lot of research on the lights in the meantime. Thanks for all the advice!

I've grown a number of things in a unit very similar to the Aerogarden, including tomatoes. You'll likely want a dwarf variety and if my experience is any indication, that tomato will shade out everything else even then. I grew a Minibel in mine and that's what happened. I had 11 unused slots because the tomato got so big. I did get several yummy tomatoes though. I finally pulled it when the tomatoes got bitter and took forever to ripen. Now my unit is replanted with greens & herbs and I'm growing Tiny Tim & Dancing with Smurfs in pots under a T5.

[Stitchingmom]

I have always started my seeds and put them in a small heated greenhouse so they would get sunlight. This has always worked spectacularly for me, but I am doing indoor growing for the first time andI am on my second set of seedlings, already. I think I might have to trash these like I trashed the first set. The first set I know I stunted because the light was too close, but I don't know what is wrong this time. I am using this light: FAMURS Dimmable TF4000 LED Grow Lights with Samsung LM301B Diodes Includes IR Full Spectrum, hung 24" above the seedlings in a grow tent. The temp is being held between 70-75 at all times, with light for 16 hours a day. I have tomatoes and cucumbers planted. They don't look as bad as the first set, but they just aren't growing again.

I just can't decide how high the light intensity should be right now. I had it about half power but a single cucumber started looking spindly, so I turned it up. I REALLY don't want to have to plant again, because I have never collected my own seeds yet, so I don't have a lot to spare of most varieties.

Any ideas?

Thanks!

An image for the product page says for seedlings to have the height at 20 to 24 inches, and the brightness at 50 to 75%; 18 hours on; 6 hours off. For non-seedlings, for vegetative growth, it says to turn the brightness up to 75 to 100% (16 to 20 inches; 18 hours on; 6 off). For flowering, it says 100% (12 to 16 inches; 12 hours on; 12 hours off). It has pictures of tomato plants by these instructions.

So, if the instructions are correct, then you need to have the lights on a couple hours longer, and you can turn it up to 75%. It doesn't sound like these lights are the super high powered ones that a lot of people have, lately (I could be wrong). How bright does it look? Does it hurt your eyes to be in the same room?

The light came with protective glasses. It is super-bright. I had it two feet above the seedlings. The first batch was getting 18 hours of light. A lack of light was definitely not the problem.

[Shule]

Huh. That's good to know. You might try making it so it's not consistently the same temperature all the time. I think tomatoes like to cool off at least a little at night.