Once the pit garden walls were done, we needed to fill in the earth back to the walls, backfill, and all also put fill into the greenhouse to bring up our growing surface and provide drainage in our cold sink / root cellar. Pit Greenhouse fill comes in all shapes and sizes. For the backfill we used the best fill we created when we excavated the hole. Then for the inside I brought home a yard of gravel in the back of the truck, and we had 6 yards of good clean top soil delivered for the garden surface.
The cover photo for this post shows the front of the pit. We used the tractor to fill the cold sink area with gravel. You can also see that we excavated a bit out of the front so that the sun is going to be able to shine through the front window when it is low on the horizon. (Discussed this in our design post) Before backfilling we put 1″ rigid insulation between the wall and the fill. Obviously this helps keep things warm in the greenhouse, but I also did this as our fill is really rocky, and I was concerned that some of the bigger rocks would damage the block walls. Adding the insulation provided a cushioning protector for the walls. Not sure it was necessary, but we had no issues with walls being damaged or moving as we filled.
Next up a door and stairs, then framing and roof. At that point, a bit of interior improvements and we’ll be ready to plant!
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