Coffee is a plant that grows in the tropics. It needs lots of sunlight and warm, humid air to grow well. However, many people grow coffee in greenhouses because they are cool environments with much lower light levels than outside. Greenhouses also protect plants from pests and other weather-related dangers such as frost or hail storms.
Can You Grow Coffee in a Greenhouse?
You can grow both Arabica and Robusta coffee in a greenhouse as long as you make sure to tailor the growing conditions to those that the plant needs. Even if it gets cold where you are, you can grow coffee trees fairly well simply by limiting the amount of sunlight to just the right level and controlling the internal temperature so that it never drops below the right numbers.
How Much Sunlight Is Needed?
Fair amounts of shaded sunlight are usually needed for coffee plants to grow. Larger plantations, impacted by weather changes, are actually growing coffee as an understory to help produce it better.
Temperature itself is usually more of an issue. Daytime coffee temperatures should be somewhere around 70-80°F while night ones should be around 65-70° or so.
Which States Can You Grow Coffee in a Greenhouse?
Technically, you can grow coffee inside of a greenhouse in every state. Some states, like California, might have energy use restrictions at times that make growing inside of a greenhouse somewhat more difficult, but it’s possible to do it in any of them.
In general, states that have temperatures that are greatly outside of what coffee needs to be grown at will cost more to run a greenhouse.
Can You Grow Coffee in a Greenhouse Year Round?
While you can grow coffee in a greenhouse all year round, you have to make sure that the internal conditions don’t change drastically. They need to be kept within certain boundaries to ensure that the plants don’t get too cold or too hot.
How Does it Do in the Winter?
Greenhouse-grown coffee will do fine in the winter, even in frigid conditions, if you don’t mind using your HVAC system to maintain a constant temperature and you regularly mist your plants. This can become energy-intensive in some areas, however.
For that matter, growing coffee in a greenhouse in environments that are too hot for it in the summer could become energy-intensive as well.
Should You Grow it Under a Taller Plant Even in Greenhouse?
Using coffee as an understory is a good idea if you’re dealing with a greenhouse environment that’s too bright for your plants. Consider planting orange or other citrus trees above your coffee plants.
Preferably, you’re going to use separate containers for your overstory plants, because many of them have the potential to change the pH of the soil. Don’t plant taller trees that are too aggressive or you could block out the sun totally.
Any taller plants should shade your coffee against the afternoon sun in particular.
How Much Does a Coffee Greenhouse Cost?
Most people who want to put up a 10×40′ greenhouse are looking at a cost of around $5,000-10,000, though they could save a lot of money by building it themselves. Commercial greenhouses, like those used to produce some types of boutique coffee blends, can cost upwards of $35,000 or even more.
If you’re lucky enough to already have a greenhouse on your property for whatever reason, then turning it into one that can grow coffee could cost next to nothing. You could also reuse a glassed-in porch or conservatory room in your home and save a bundle that way.
How Much Work Is it to Grow Coffee in a Greenhouse?
Once you have all of your seedlings transferred to their permanent growth containers, it shouldn’t be any more work than caring for coffee in any other situation. You’ll want to be sure that you’re diligent about misting your trees, however, because they can get dry rather easily.
Cleaning up any soil that makes it onto the ground is important as well, but this again shouldn’t be any more work than if you were growing coffee in a more traditional garden space.
How Much Coffee in Pounds Can You Grow in a Greenhouse?
Each mature coffee plant can produce just around a single pound of coffee each year. That translates into about 45 six-ounce cups, so you can use this to calculate the amount of coffee you can grow in your greenhouse easily.
Simply add up the number of plants you have that are producing mature berries and you should know how many pounds of coffee your greenhouse can put out each year.
How Big Does the Greenhouse Need to Be?
Every coffee plant you put in needs to have around six feet of protective space around it from any other plant in its row. Additionally, each row in your greenhouse needs to have another gap between them.
If you’re growing sufficient amounts of overstory like orange trees, then you can grow them much closer and make better use of the space in your greenhouse. You might also consider growing them close together if you have a variety of Arabica that tends to shoot upwards more than out.
Do Different Varieties of Coffee Do Better in Greenhouses in Different Lattitudes?
How to Grow Coffee in a Greenhouse
First, you need to make sure that your greenhouse isn’t going to receive much in the way of drafts then you can:
- Create a humid environment between 60-70°F
- Provide a shady environment lit with diffused light inside the greenhouse
- Pot all containers you plan on using with loamy soil
- Add humus and peat moss to the pots
- Maintain a neutral pH balance of the soil
- Mist all of your coffee trees
- Transplant seedlings that are 24-36″ in length into permanent growth containers
- Drain soggy soil to prevent mold growth
- Provide a weekly feeding with nitrogenous foods
- Gently remove any dead or diseased material that makes its way over time
- Plant other trees, if necessary to serve as overstory in order to control light
- Do not attempt to harvest the plants until at least 24-48 months have passed to allow them to enter maturity