Welcome! If you're here to learn about greenhouses, we're glad to see you! We are publishing a series of posts on DIY gardening - from setting up your greenhouse, to planting seeds, to transplanting, to growing and harvesting!
Next post is Planting Seeds
Coming soon is Transplanting the Seedlings
Every year we buy a LOT of plants. Tons of annuals, some perennials, and a few for the vegetable garden. The local nursery loves us! We get plenty of frequent flyer points there.
But we thought it would be fun to make our own - maybe we could save some money, it seems easy enough, and we could get exactly what we wanted. We've grown a few in the house, but there are only so many window sills to go around. This is where the greenhouse comes in.
Choosing a greenhouse
I'd been looking at greenhouses for a while. There are lots out there. From simple domes over the top of containers, to inexpensive plastic sheeting on pipes, to more sturdy (and more expensive) polycarbonate and glass greenhouses. Some models are single walled, some are double walled.
They all have their good and bad points - for me much of the decision focused on cost and size. We needed enough room to be able to grow the number of plants we need, but I did not want to spend thousands, and I didn't want a bunch of wasted space. At the same time, I did not want something that felt disposable. I was going to put it up and leave it up.
A variety of the less expensive options I saw on Amazon. Any of these can be good depending on what you need. You just have to keep in mind how sturdy it will be in various conditions.
Cost was an important part of the decision. I like hobbies but I am not allowed an unlimited budget. If I was spending more to grow the plants than I was buying them from the nursery, it would be tough to convince Mrs. Folks. That said, the initial investment is the hardest part. It will take a couple years to recognize any savings on the plants we grow ourselves. So we wanted to balance quality with cost.
I did a fair amount of reading online and also bought this great beginner book by Jason Johns - "Greenhouse Gardening - A Beginners Guide To Growing Fruit and Vegetables All Year" which was helpful in deciding what was important for our needs and what I then had to purchase. He also had a lot of great info about certain types of plants and how to make them work in a greenhouse. Tomatoes can be particularly challenging.
After all that, I decided on the Palram Mythos Hobby Greenhouse, in the 6x6x7 size (note: this listing will let you choose different sizes)
Twin wall polycarbonate added some insulation to the outer walls
Aluminum skeleton and galvanized steel foundation should be long-lasting
Good amount of head space, and lots of room for shelves.
Roof vent makes it easier to cool the greenhouse in the summer.
Building the Greenhouse
Once the package arrived, we were committed. First I wanted to create a flat space for it and get the greenhouse off of the ground. We also wanted to give the greenhouse a stable base to fasten into. Some of the reviews indicated that people had issues with wind, I figured a good foundation would help. I wanted to position the greenhouse next to the garden but without blocking any of the sun. We cleared a spot just north of where the garden would be, and dug down a few inches. We lined the hole with weed block and filled with pea gravel. The foundation was made of pressure-treated 4x4s, with half-lap joints on the corners, and using 3/8" x 12" rebar to hold them down. We did make the foundation slightly larger than the base of the greenhouse so we would have plenty of wood to screw the greenhouse into.
Once we had somewhere for the greenhouse to go, we spent the weekend following the 55-page instruction manual. You can tell the manual is designed for multiple countries - mostly pictures in the Ikea style. But we took our time and didn't really have any trouble with the instructions. We also took our time to separate the components and hardware so we knew what to look for. Our only issue was the weather - it decided to rain all weekend. Luckily we had a canopy that we could use to keep us dry-ish until we got the roof on! Check out the slideshow for all the action.
Powering the Greenhouse
Once the greenhouse was up, I wanted to have power in case I needed it. I was thinking of lights, heaters, fans, warmers and other things. I read up on various solar components, including large panels, chargers, batteries, converters, and all the things you might need if you were doing a 12v solar system. It would have been fun, but in the end, it was cheaper and (maybe) easier to simply dig a trench and pull a 110 line from the power I had at the deck. For the distance and the fact it was being buried, we used 12/2 UF wire, and put it in 3/4" conduit. Once in the greenhouse, a weather tight box, weather tight outlet cover, and GFI outlet was put in place to ensure the circuit would be protected if it ever got wet.
Please note that the rocks tried to stop us from doing this. Many giant rocks were uncovered, and one was so big we just had to go around. Huge props go out to #3 and #4 daughters who actually did most of the digging!
Creating space for plants
Next we had to have a place to put the plants. I had been thinking of some sturdy shelves. Now these weren't going to be wet so we just used some douglas fir 2x4s and 4x4s, using lap joinery and pocket screws to hold them together. I did not like the idea of solid shelves. I wanted to allow the maximum amount of light and air movement through the greenhouse so we used 1/4" hardware mesh for the shelf tops, and just stapled those down.
Planning ahead
We also added a few things for when the greenhouse warms up. If you're doing any growing during the summer these are key.
Palram automatic roof vent opener - a little piston that expands when it gets warmer to open the roof vent
Shade cloth - drape this on top of the greenhouse or hang it inside to bring the temperature down
Temperature Controller - a thermostat that can control both heaters and coolers. (Another popular use for this one is for home brewing)
Exhaust fan - helps keep the air circulating and moving the hot air out. When I install this one it will be a separate post.
A few lessons learned
We did try to get some plants going that first year, but it was a little late when we started.
Timing is key to planting. It's important to pay attention to the dates on the seed packets. We had some that didn't flower correctly or never quite flourished.
We also learned that the light coming in through the greenhouse seems like a lot, but it's not enough. You end up with long, skinny plants - commonly described as "leggy". Grow lights will help here.
Putting a fan on the plants will help their stems to get stronger. Doesn't need to be high speed, just enough to simulate a breeze.
Stay tuned!
We just published a post on how to get started planting seeds! Click here to check it out.
Questions? Comments? We'd love to hear from you. Leave them below!
Comments