Build an Indoor Greenhouse Part 1

If you like fresh vegetables this is for you. Every week when the wife and I go grocery shopping we spend quite a bit of money on vegetables. What we don't use gets blanched and frozen then if possible I harvest the seeds. My goal was to find a way to grow the seeds indoors and have access to fresh vegetables indoors. This way I don't have to dig up my yard, I can see and pick the vegetables as soon as they are ripe, I can plant earlier, and the bugs and critters don't bother the plants.
After thinking on it for a bit I decided I would build a mini green house that is small enough to be moved but big enough for the plants to mature in with no need for electrical equipment. Don't forget to check out Part 2 for the store bought control and info on sprouting seeds easily.

  • Plastic tote
  • Dirt or potting soil if you don't have good dirt
  • Popsicle sticks
  • Vapor barrier
  • Packing tape or duct tape
  • Seeds
Build the damn thing

Step 1. Mix up some dirt. Pick out all the
rocks and sticks and shit. Mix in compost if ya
want. Put about 4" of good dirt in the tote.

Step 2. Cut some popsicle sticks in half and
write what you will be planting. It is easy
to forget what got planted where so I
always mark it out.

Step 3. Get some seeds
planted. Not much to it.
Either dig a small trench
1/2" deep or put the seeds
in one by one. 


Step 4. Cover the seeds and make sure you
mark them. Water the seeds now because
the tote needs to stay sealed for 5 days.

Step 5. Drill a hole in the side of the tote and
put a plug in it. This will let you water the

Step 6. Cut a piece of vapor barrier for the top
of the tote. Make sure to cut it bigger than you

Step 7. Wrap the top of the tote in vapor barrier
and tape every seam so no air leaks. This is
important during germination. After the seeds
sprout you can make a removable cover. You
shouldn't need to water for the first few days
as long as the dirt was moist.

Done. Put the greenhouse outside or in a sunny window daily and bring it back in when it gets dark. Pretty simple to build. Don't open it up for at least 5 days. The seeds will germinate faster if you do not open it up. I put a reptile thermometer in the green house so I could monitor the temperature. Later on I read ambient temp isn't as important as soil temp so I moved the thermometer to the soil. It is important to check the temp because the greenhouse gets hot fast.
This was the ambient temp after about an hour in the sun with
an outside temp of 61 degrees f
I planted green bell peppers, jalapenos, serrano peppers, and red peppers. These are all plants that do best in heat so temp isn't a big concern until they sprout. If you have other plants growing in the greenhouse check the temps and moisture they need. 
Alright now that the green house is built and you see the first sprouts growing it's time to build a removable cover for the tote. If you have the lid that fits the tote just cut the center out and glue or tape plexiglass or vapor barrier over the hole. You could also just keep taping the original vapor barrier cover back on but I lost my patience with this. The tote didn't have a cover so I built a removable one that will seal everything up well.
  • A few scraps of wood
  • Vapor barrier or plexiglass
  • Wood glue
  • Caulk
  • 1 5/8" screws
Build the damn thing
Step 1. Measure your tote
Step 2. Rip down four pieces of lumber to 2"
Then cut them to the size of your tote. In my
case the tote was 16 1/4" x 22 1/2" So I cut two
pieces at 16 1/4" and two at 24" to account for the
thickness of the boards


Step 3. Glue and screw it
Step 4. Set your tablesaw and rip 4 boards to 1 1/2" Then cut the to the length of the frame. I needed two at 24" and two at 14 3/4" if I remember right.
Step 5. Run a thick bead of caulk around the
whole top edge of the frame. Make sure the 
edge gets evenly coated. Then cut a
piece of vapor barrier about a foot bigger
than the size of the tote.

Step 6. Use a few clamps to position the top
trim pieces where ya want them.  Next screw the
trim pieces on don't glue them. You want the trim to
be removable in case the plastic needs to be

Step 7. Trim the excess plastic to about 1/4"
over hang and smooth the excess squeeze out
from the caulk

The cover you built should be a very tight fit.
A nice thing about this design is its free/cheap
 and the plastic is replaceable.

Heres another easy mini greenhouse. Cut the top
off an egg carton. Set the bottom on the top. Mark
it. Fill it with soil. Put the seeds in. Wrap it in
plastic wrap. Done.

My results so far
Ok everything is built and now the plants are starting to grow. The whole setup should take care of itself for the most part and it won't need to be watered too much. Here' my finding after five days with a daytime high around 60 degrees f and  bringing the greenhouse inside at night. Ambient temp inside the greenhouse was between 80 degrees f and 110 degrees f for most of this time
Day 1- Nothing
Day 2- Nothing
Day 3- Some of the weeds and grass from outside are sprouting. I watered today.
Day 4- One red bell pepper looks like it broke through
Day 5- Up to one red bell pepper 1 serrano, and 2 green bell peppers. These might be lookalikes though because I didn't use sterile soil.
Day 6. Bunch of little sprouts from outside plants. It looks like another bell pepper is sprouting
Day 7. Two more green bells broke through
One of the pepper sprouts at day 5...maybe
All the seeds I used were harvested by me from fresh vegetables. I used no special potting mix, fertilizer, or compost. Fortunately we have very good black dirt around here. The greenhouse is self contained, I've only watered it once in the last 5 days, and it uses no fans or electricity at all. I'll let ya know how its doin in a few weeks.

Heres Part  2

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