So, you have decided to build a greenhouse, but you are confused about which type of greenhouse covering would be best for you. Let’s take a look at some of the pluses and negatives of polycarbonate sheets and polyfilm coverings. We will discuss R value, installation, cost and lifetime expectancy.
R value is defined as a materials ability to resist heat flow. The higher the R value, the less energy it will take to heat the same size space under equivalent conditions. This may or may not be a concern to you depending on how you are going to use a greenhouse.
The most common single film used for greenhouses is clear 6 mil, 4 year covering. What this means is that the film is 6 mil thick and that the UV protection is warranted for up to 4 years. There are also some other types of film such as overwinter (this film is meant to last one year), white films (lower light transmission) , and reinforced polyfilm (with a rip stop cord).
The R value of single polyfilm is 0.87. It is the least efficient of all of the greenhouse coverings we will discuss.
Installation can be done in several different ways. If you have a wood frame you can use batten tape and staple through the cover and the tape into your frame. If you have a wood frame or a metal frame you can use the base and wire system. The base is screwed to your frame and the cover is secured using a W or wiggle wire. This is a pretty simple installation, but you want to make sure that you do not try to do this on a windy day. You will need several people to do this depending on the size of the greenhouse.
The single polyfilm will be the least expensive of all of the coverings we will discuss.
This film should last you the 4 years that the UV covering is guaranteed for. The only issue with this covering is that you may get a tear. There is repair tape available for this. But, if you are not there and not able to fix a tear in a timely manner you may lose the entire cover. This is why some people will choose to go with the reinforced polyfilm over the clear 6 mil, 4 year. It has a rip stop cord that will keep a tear from spreading. That way you will be able to fix the tear no matter how soon you are able to get to it.
Reinforced Polyfilm with Rip Stop
You can do a double polyfilm greenhouse a couple of different ways. You can just buy 2 pieces of the film and attach them together. Or, the easiest way to do this is to buy a tube of the polyfilm. This is just a double layer that is already fastened together. The base and wire system is set up to hold up to 6 layers, so this is not an issue. You will also need a poly inflation fan kit to inflate the 2 layers. I have had some people mention that they think this makes the cover tighter and less susceptible to tears. I have no proof of this, but it does seem a logical conclusion.
The R value of double polyfilm is 1.7. This will save you 40% on the energy costs over a single layer of polyfilm.
The installation on this is done in the same manner as a single layer of polyfilm.
This film will basically be twice the cost of the single polyfilm, as you are basically just using a double layer of the same material. You will have the additional cost of the blower fan. These are typically around $200 or less, depending on the size of the greenhouse and the size of the motor needed.
This film may last a little bit longer than the single layer. As I stated earlier some claim that they inflation keeps the film from tearing as easily. The UV protection is rated for the same amount of time as the single polyfilm.
Polycarbonate is the greenhouse covering of my choice. It fits my needs the best of all of the materials. However, a lot of people don’t like it because of its appearance. It is a rigid plastic configured in much the same way as a piece of a cardboard box. It has a sheet on the outside, a sheet on the inside and a rib that runs through between the 2 sheets. The rib in polycarbonate will be straight vs the wavy rib in a cardboard box. This will distort your view. You will be able to see color, but you will not see form clearly. I use the example that you can see a green leaf and a red flower, but you will not be able to make out if it is a poinsettia, geranium, impatiens, etc. Of course the clear polyfilm is not exactly clear either. It will have a hazy type of appearance to it. If you want a clear glass like view, tempered glass is your only option.
Polycarbonate sheets are available in several different thicknesses. 8mm clear twinwall will have an R value of 1.8. 16mm clear triplewall will have an R value of 2.4. This will be the most efficient of the coverings we are discussing.
Installation of this material requires polycarbonate H profiles to join the sheets side by side and polycarbonate U channels to close off the ends. You will need more framing for this material vs polyfilm greenhouses. Typically polyfilm greenhouses will have 4′ or 6′ wide spaced bays. You can do the same with the polycarbonate, but you will need to run purlins between the rafters spaced according to your snow load needs. There are charts available to determine this. You can typically install this with 2 people as the sheets are not heavy and you install one 4′ wide or 6′ wide sheet at a time. You still do not want to try to install under windy conditions as the sheets can be caught by the wind and sail away.
This will be the most expensive of the coverings discussed in this article. But, it will be the longest lasting. Depending on the manufacturer polycarbonate sheets have between a 10 year and 20 year warranty on the UV. Most sheets also have a 10 year warranty on hail damage, so no need to worry about tears. The practical life expectancy of this material is 20 – 25 years.
When considering which of these materials to use to cover your greenhouse you should look at the initial cost, the cost to install, the cost to heat the greenhouse, and the life expectancy of the material. Once you have made these decisions you should be able to choose the best covering for your greenhouse with ease.
Growing vertically is an excellent option when your space is limited and you are looking to increase your yield. There are some plants that naturally grow vertically, but there are also planters where you can “stack” your crops to save precious space. Let’s take a look at some of these.
Why Grow Vertically?
Well, there is the obvious point that I have already discussed about saving space. But, believe it or not there are other advantages to growing this way as well. Harvesting is easier. You do not have to bend down the entire time you are picking. Plants are healthier and give higher yields. There is greater air circulation around the roots and greater exposure to light.
Probably my first exposure to growing vertically was a strawberry tower. I used one of these about 30 years ago to grow my herbs. I totally enjoyed it. Today there are so many different type of vertical planters.
There are pouches with pockets sewn into them for individual plants, similar to a shoe holder. In fact I have even seen articles where people recycle and use their old shoe hangers for this. I think I would be careful with this, you want the holder to be of a breathable fabric. In my mind I see old style shoe holders made out of rigid plastic.
There are planters where it appears that pots have been strategically stacked on top of each other. A nice feature to look for in this type of planter is to see if there are any wheels or a cart below it. You may need to turn the container to get all of your plants the needed sunlight. If you are growing indoors you can probably set up your lights so that this is not a problem.
You can take an old set of stairs and add planter boxes to each step. This is a picture of a herb/flower garden combination I did a couple of years ago.
My Herb Garden
Yet another way to recycle pallets. You can close off the back, sides and bottom of the pallets with landscape fabric. Put your soil between the exposed slats and plant your plants. I would leave this lay flat on the ground for a week or so allowing the plants to become rooted and established. That way they will not droop or potentially fall out when you hang the planter.
Growing with trellises, supports
There are some plants that want to grow vertically naturally. These would include tomatoes, beans, cucumbers, etc. You should supply them with support whether you are growing in a container or in the dirt. Make sure that your support is sturdy and securely fastened. You can purchase trellises or you can recycle and make your own. I have watched my husband go into our woods and come out with three sticks of the approximate same size. He placed them in a tepee type configuration and wound this together with rope. He says this is something he learned in the Boy Scouts. I am not sure of that, but I am sure that it was virtually free (the rope was laying around but it had been purchased at one point) and the plants loved it and did well.
If you are growing these types of plants in containers make sure that you have a large enough container for the job. There are some tomato planters out there that are all set up except for the dirt and the plant. Some of them even have lights so you can use them inside.
There are quite a few hydroponic systems out there that have multiple layers. These can be purchased, but I sure that they can be a pretty easy diy project as well. These systems are great because you get more food in less space as with all of the vertical systems. But, hydroponic systems have a tendency to have an increased yield over some other growing systems. Plus, crops will grow faster, harvesting is easier, you have less pests and disease with these systems. And you will have less problems with pets and wildlife with the systems, especially if you are growing them indoors.
Be sure to plant your bigger plants, or plants that tend to droop toward the bottom of “stacking planters”. You do not want these bigger plants hanging down and shading your smaller, more upright plants.
Use potting soil that is not as heavy as regular soil. You want to use the same type of soil as we recommend with any container gardening. You want a soil that will not dry out too quickly. You need something with peat moss, perlite, etc. Something fluffy.
Be very careful about how you set up your water. Of course with hydroponic systems or stacking systems watering is usually an integral part of the set up of the system. Let’s say that you are hanging pouches and planters from a fence wall or an exterior wall on your house. You want to make sure that you have the watering set up so that it does not lay on or run down the wall. You do not want to cause any water damage or leave water streaks on the surfaces.
Plant crops with similar needs such as having the same growth rate. This will ensure uniformity in your vertical garden. Also, consider plants with the same needs regarding sun vs shade. Make sure that your containers are not shaded by another structure if they are outside.
Make sure that you hanging planters are securely fastened. Also, check roots periodically to make sure that they are not growing into siding or just becoming a problem in general.
If you are growing inside be sure to set up your system in a sunny area, or supply them with the proper type of lighting. Options available are LED (light emitting diodes) lights, HID (high intensity discharge) lights and fluorescent lighting.
“I don’t have enough room to grow my own food” is definitely not an acceptable response anymore. Take advantage of one or a mix of these vertical growing systems to grow food for you and your family year round. Tammy
I am thrilled to announce that Amazon has approved us for their infuencer program. Through this I am able to share my personal recommendations for gardening products. I have spent the last week scouring Amazon deciding which products were worthy of this page. A lot of the products are items that I have used personally. Some of them are items I have sold before and had positive response on them. Some of the products are items which I have seen while attending trade shows. And finally, for the items I was unfamiliar with, I studied all of the reviews to decide if I thought they were good enough to make the cut. All items are garden related, although some of the items are just a little bit whimsical. Gotta have a little fun while digging in the dirt. Oh yeah, and this is an affiliate program. We will get a small commission on any item which you buy from Amazon as long as you start your search on this page. Any help is appreciated. This is part of what helps us to be able to supply our free content to you. Check it out and see what you think! Tammy
Do you want to grow vegetables and herbs indoors? Unless you are growing a few plants such as herbs on a sunny windowsill, you will definitely need lighting. If you do not use grow lights your plants will become leggy and spindly. They will not develop a healthy root system and let’s face it, they will probably never produce into the food you are looking for.
Trying to grow tomatoes in a greenhouse in the short winter days? You will need supplemental lighting. There are a lot of different lighting options available. Let’s take a look at them now.
Different types of lighting
There are basically 3 types of lamps available. They would be HID (high intensity discharge), LED’s (light emitting diodes) and fluorescent fixtures. There are a couple of sub categories in each of these categories.
HID lamps are twice as efficient as fluorescent bulbs. They are available in several different sizes from 250 W to 1000W. If these are used as a primary light source a 250 W fixture will cover an area of 3′ x 3′. A 400 W covers 4′ x 4′, a 600 W covers 6′ x 6′ and a 1000W covers a 7′ x 7′ area. You should place your fixtures as close to your plant as possible without getting it too close. The HID lights put out a lot of heat. The best way is to put your hand under the light at the desired height. If it is not too hot for the back of your hand it will be OK for your plant. HID lights come with metal halide (MH) or high pressure sodium (HPS) bulbs. The metal halide is for the vegetative or growth stage. It supplies a blue range of light that is similar to what we have in Spring. The high pressure sodium is for the fruiting or flowering stage. It supplies light in the red range. These systems come with a ballast. It used to be that we had to have one ballast for each type of bulb. But now there are switchable ballasts available that will work with either type of lamp.
Historically fluorescent lights were thought of as to be used with seedlings or plants that did not require as much light. But, that has changed with the development of HO (high output) T5 lamps. These are only about 5/8″ in diameter. These high output lights will give twice as much light as the standard T5. They are able to produce enough light for larger or fruiting plants. Of course they will be more expensive than the standard fluorescent lamps. They are available in 2700K(yellow, red light) for flowering or 6500K (full spectrum light) for plant growth. Fluorescent bulbs are also available in T 12, T8, T5 and compact fluorescent models. They are not as efficient and may be best left for seedlings and low light plants.
Fluorescent lamps have several benefits. They are lightweight, affordable and easy to assemble. They do not put out much heat at all. These lights should be placed within 4″ to 6″ of the top of the plant.
LED lights have historically been very expensive and pretty much out of the range of the non commercial grower. But the prices have come down considerably in the last couple of years. The price on LED lights is still typically higher than the other types, but they will definitely cut down on the electric bill. They use half the electricity of HID and fluorescent lighting and will last up to 5 times as long. Most of these lights have a small built in fan which means they will run cooler.
There are full spectrum lights available where you can switch the growing mode. This is much the same concept as the switchable ballasts for the HID lighting. You should check the manufacturers specifications for coverage area and height to hang these fixtures. They are typically hung 18″ to 24″ over the plant.
How Long Should You Leave Your Lights On?
I know everyone hates this statement, but it is something you will need to experiment with. It depends on if you have any other light source and what type of plant you are growing. If you are using it as a primary light source growing inside I would recommend starting at 14 – 18 hours for the growth stage. Once you are fruiting or flowering you can cut this down to 12 hours.
If you are using the lights for supplemental lighting in a greenhouse you will not need them on during sunlight hours. The way we always did this was to have our lights come on 2 hours before sunrise and then turn them off. At night we would turn them on at dusk and leave them on for 2 hours. Of course this is all easiest to do with an automatic timer.
What can I grow using grow lights?
With the proper setup you can grow just about any crop under grow lights. One thing to take into consideration is what kind of space will you need. It is probably not practical for most of us to try and grow crops like corn or watermelon inside. A few examples that do well include tomatoes, lettuces, spinach, herbs, peas (will need to be trellised), bush green beans, bush cucumbers, broccoli, cauliflower, beets, carrots, radishes, etc. Keep in mind that you must meet the same temperature requirements that these plants need outside. For example, you cannot grow cauliflower and broccoli in an 80 degree room. You cannot grow tomatoes in an unheated basement in the winter.
Just because you don’t have a yard and it is the cold of winter does not mean that you cannot have fresh herbs and vegetables for dinner tonight. Set aside a little space and try growing some food indoors under lights.
A lot of people wonder if composting is really worth their while. If done properly it really takes a minimal amount of effort. I am not saying you don’t have to work at it, but you don’t have to work at it hard. You just need to follow the “rules” and you will get an excellent product to use in your garden, your containers, or even your flower beds. Plus, let’s face it. None of us wants to contribute any more to the already overflowing landfills than we need to. Just think of it as doing your part to help Mother Nature.
Over 1/3 of the materials in a landfill are compostable. Why are we throwing out these items that we can turn into the best amendment for our gardens? Do we think it is going to be too hard? I don’t know, let’s not over think it. Composting is simply the breakdown of organic matter. Nothing more, nothing less. Compost fuels plant growth, while restoring previously depleted soil. It also helps to retain soil moisture and helps to hold off plant diseases.
What Will I Need to Compost?
There really is not much start up cost and you can get as fancy as you want. To start you can use a small roll of fence that you can purchase at any local lumber store or home store. You would also want to have a few posts to wrap the fence around to make your “bin”. Or, you can recycle pallets to make a compost pile. The most expensive, but probably the easiest way is to use a tumbling compost bin, but they will be the most expensive initially. There are also worm composters available. The worms do the breaking down of materials in these systems, no turning with them.
If you are doing any other method than the rotating bin or worms (vermicompost) you will need something to turn the pile with. We had a special compost turning tool at one point, but a shovel or hoe would work just as well. A neat thing to have on hand is a compost thermometer. You can take the temperature of your compost pile and brag to all of your neighbors how hot your pile is. (I know, a little too geeky for some). This is also a nice tool to help troubleshoot as you rill read below. A really nice item to have is a decorative bin to place on your kitchen counter to collect scraps. You then just take this to your pile every day.
Other than that you need your browns and greens. I remember reading an article in a gardening magazine years ago. The author was telling you if you did not have enough garbage to use OPG (other peoples garbage). I guess some of your neighbors and friends would be willing to do this if you share at the end. I have also read about people going to produce departments and getting the produce that goes bad. The stores are usually glad to give you these unsalable items. That way it doesn’t have to go to complete waste.
What to Compost?
If you have checked into composting before you have probably seen the terms “green” and “brown”. These are referring to the 2 sets of materials that should be added in proper ratios to your compost pile. The green items supply the nitrogen and the brown items supply the carbon. You should use a ration of 1/3 green to 2/3 brown.
Hay or Straw
I do not recommend using cheese or meat scraps for your compost pile, as these attract rodents. Leaves and larger items should be shredded prior to being placed in your compost bin. If you have too many leaves in the fall you can just save them to the side and add them to the compost pile as needed. Meanwhile they will be partially breaking down. Be sure not to add big clumps of any of the items you are putting in your pile. You want everything to be loose .
Maintaining your pile
Don’t leave food scraps at the top of your pile. Cover them with a layer of leaves or grass. This will help to deter pests (rodents, raccoons, etc) that may want to get into your compost. You need to rotate every few weeks and add in more materials. You should be keeping your pile moist, not damp. Or, if you have purchased a rotating bin you should follow the instructions that have come with the bin. These are usually up on a stand and are easily rotated with a handle or simply by spinning the bin.
Troubleshooting Your Compost
Your compost pile should not smell. If it smells like rotten eggs or musty you need to add browns and aerate it (turn the pile). If your pile is not getting hot enough add more greens. This is where your compost thermometer comes in handy. Your pile should be getting to at least 150 degrees F if it is working properly. If your pile is too wet, add brown – cardboard, leaves or wood chips.
Bugs, etc in compost pile
If you have mites it means that your pile is too moist. You need to add your brown materials. You may see a white layer form over your compost pile. It is fungus and will aid in the process. It should be ignored. You may also see millipedes and potato bugs in your pile at times. There is no concern as they are just aiding in the process. If you have rodents you should make sure to “bury” food scraps below the surface of the compost pile so they are not quite as tempting to the animals.
When To Use Compost
Most people agree that the fall is the best time to add the compost into your garden soil. Cover it with some sort of mulch. That way it will have the entire winter to break down and become part of the garden bed. If this is not possible or you just don’t want to do it then you can add it about 2 weeks before you are ready to plant. Be sure to mix it into the soil good. Of course most of us are in a big hurry in the spring to get planted, so waiting until you can work the soil and then waiting 2 more weeks may be too much for some of us (pointing at myself).
Heating the greenhouse with compost
Did you know that you can use your compost pile to heat a greenhouse? You can put the compost pile directly in the greenhouse if you have space. Remember that they will get up to 150 degrees when working properly. Use your thermometer to check the temperature. If it is lower than 120 degrees you will need to aerate the pile. Some people are concerned about having their compost bin inside the greenhouse due to the potential fire hazard. Plus, I have heard the complaint that the pile may smell. If you recall from earlier in this post, if you have a smell you need to fix your compost bin – something is wrong.
If you prefer to have your compost pile outside the greenhouse you can run water pipes through the compost pile to heat the water and then run the pipes into your greenhouse.
Composting is a win / win situation. It is good for your garden, good for the planet and good for your soul. Get busy composting!
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