Too much sun too soon?

[enchant]

I planted my seeds about 10 days ago. Most seedlings are now nearly 2" tall and living under a grow light.

It's still chilly outside. Even though it's a bright sunny day, temps are only in the upper 40's.

On an impulse, I recently bought this plastic greenhouse from a local dollar store for $20. It's about 2' square and 5' high, covered in clear plastic. Today I put it out on the back deck and put a thermometer in it. And although the surrounding air is under 50, it's almost 80 inside, in the shade.

But is this too early for direct sunlight on my infants?

[zeroma]

Even inside a greenhouse, they need to be hardened off and not just suddenly moved into different conditions. So yes.

Also, when you are ready to plant them outside, remember that they will need to be hardened off from the greenhouse to outdoors - inside the greenhouse is still a protected environment. Hardening off is going to give you the best results when you transplant for sure.

[carolyn137]

Originally Posted by enchant

I planted my seeds about 10 days ago. Most seedlings are now nearly 2" tall and living under a grow light.

It's still chilly outside. Even though it's a bright sunny day, temps are only in the upper 40's.

On an impulse, I recently bought this plastic greenhouse from a local dollar store for $20. It's about 2' square and 5' high, covered in clear plastic. Today I put it out on the back deck and put a thermometer in it. And although the surrounding air is under 50, it's almost 80 inside, in the shade.

But is this too early for direct sunlight on my infants?

It's not the sun alone that's the problem as I see it,it's using one of those plastic greenhouses with covers,and even inside with no air circulation the temps get too hot and the seeds are cooked.

My suggestion is to get them out of the cooker and back under the lights, be sure there's good air circulation and keep the lights no more than a couple of inches from the plants,if not you can also burn the tender new leaves as well.

Keep raising the lights as the plants grow and let them get to maybe 3-4 inches tall before potting them up,just ONCE,before starting the hardening off process.

Carolyn

[enchant]

Originally Posted by carolyn137

My suggestion is to get them out of the cooker and back under the lights,

I never put them in the greenhouse. I simply put the empty greenhouse outside with a thermometer in it.

Around lunchtime, the temperature in the greenhouse was over 100, so I'm not sure how I'm going to put this greenhouse to good use.

[pecker88]

Originally Posted by enchant

I never put them in the greenhouse. I simply put the empty greenhouse outside with a thermometer in it.

Around lunchtime, the temperature in the greenhouse was over 100, so I'm not sure how I'm going to put this greenhouse to good use.

W/out ventilation that greenhouse is a plant cooker.

At a minimum, you could try and keep the door open, and put it in a location that only receives a few hrs of morning sun. W/out some type of shade cloth over the greenhouse and/or ventilation, after 2 hrs of full sun, regardless of the outside temp, it will be too hot in there for anything but a cactus.

[carolyn137]

Originally Posted by enchant

I never put them in the greenhouse. I simply put the empty greenhouse outside with a thermometer in it.

Around lunchtime, the temperature in the greenhouse was over 100, so I'm not sure how I'm going to put this greenhouse to good use.

This is what I missed, as you wrote

(It's about 2' square and 5' high),

What I missed was the 5ft high,reading too fast maybe, so now I understand,one of those mini hot houses with a flap to enter.

Does it have sides where you can roll them up to allow for ventilation, or same in the back?.

Carolyn

[enchant]

Originally Posted by carolyn137

Does it have sides where you can roll them up to allow for ventilation, or same in the back?.

No, the sides and back are pretty much unmovable. The front unzips on both sides and can be rolled up.

[carolyn137]

Originally Posted by enchant

No, the sides and back are pretty much unmovable. The front unzips on both sides and can be rolled up.

OK, in the daytime unzip the front and roll it up, put a fan in there if you can, I'm sure it's a very narrow aisle ,to keep air circulating, putting it against the back, before you go to bed, shut off the fan rezip, and say goodnight to your plants.

I don't know,you didn't indicate what zone you are in near Boston, but isn't it perhaps a bit early to be starting seeds,etc.?

Carolyn

[MissS]

No it is not too early to expose your plants to sunlight. In fact, the earlier the better. However, you should acclimate them to the sunlight gradually. First put them in a bright but shaded spot. Then gradually expose them to the direct sunlight for an hour or two a day and allow them a little more time in the sun each day for a week to 10 days until they are comfortable in the sun all day. Watch the temperature in the greenhouse so that you do not 'cook' them.

[enchant]

Sounds like it was an ill-conceived purchase. Oh well - it was only $20.

[mikemansker]

I have a couple of those greenhouses and I use them every year. I start plants indoors in them under a grow light. When the plants get a little bigger and the weather is a little warmer, I move everything outside on the south side of the house protected from the wind. Mine have a front panel that zips and you can roll it up to provide circulation and keep the temps down. Of course you have to use your head. I have a few trays that I can move inside if it's going to be too chilly at night.

Plants will also dry out pretty quickly, so you need to keep up with watering.

[pecker88]

It took me awhile to get my greenhouse temp's dialed in, it's not easy.

It's currently 57 deg. outside right now and 100% overcast. I have the 30 ft long side of the greenhouse open 1/2 way, about 20 inches and it's still 80 deg. inside. Since the wind is blowing from the North at 10 mph, that side is closed.

I also have 40% shade cloth over the area where the seedlings are, just so they don't get burnt, because I leave them out there 24x7. Night time lows are 30-40's, propane heater set to 60.

[dmforcier]

Try it in January.

[oakley]

I have one that is 6x8 and built really well. Been out for three years in all weather and
feets of snow, next to the house by the garage.
Impulse purchase 50$ on close out at HD.
In our climate it has not much use. Too cold at night and hot daytime temps.
Impossible to regulate temps. I may use it for overflow this year, but now it holds extra
garden supplies, garage overflow, and the worm bin composter. A big bag of peat.

If you have a spot with just an hour of morning sun but mostly shade it can work with
the door open halfway all day, then close at night. Still just too much temp fluctuation.

I have so many extra plants right now that i may experiment as many of those are
headed to the compost anyway.

They may be useful for some plants, but not so much for tomatoes.
65 today, really nice day and sunny. That thing is a sauna. With vents open.

[BigVanVader]

I'm going to chime in and just tell you how I do it. I don't harden off plants like most. I take them from under lights to the coldframe with no special treatment. I leave my ends open so I get a very slight breeze and the temps stay just a little above outside. I'd say 95% survive and the 5% is from wind breaking the stem, and I consider that a needed culling of the weakest.