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Tips for Creating the Perfect Greenhouse for Growing Food

There are many complexities of greenhouse gardening that confuse people today. However, many of the rules and regulations that cause the most confusion are ones you can simply forget about. To have a really well cultivated greenhouse you simply need to use some real soil, add plenty of light and air, water when necessary and nourish the plants.

Tips for Creating the Perfect Greenhouse for Growing Food

When you stop investing in chemicals you'll have more money for additional plants. You'll also find the problems you were facing (e.g. disease, insects, weak growth, below average performance) are symptoms of improper cultivation. These aren't a problem after you zero in on the basics.

Soil, Air, Light and Space

Do you have a green thumb? If not, or aren't yet sure if you do, make sure you only grow vigorous plants that are disease resistant (e.g. Heirloom tomatoes). This means you don't want to grow plants that need to be constantly fed or plants that succumb to aphids.

The best type of soil for your plants to grow in is equal parts of rich garden loam, compost, and peat moss or, at the very least, a half-and-half mixture of the compost and loam. Regardless of how you mix the soil, you'll want to add six inches of it along with four inches of either bone meal or wood ash. When the loam you're using contains clay, make sure you also add in some sand.

While the soil is important, so is the amount of air your plants receive. This is because things like pests, fungi, mildew, and diseases attack plants that don't get enough air. To prevent this from happening, make sure your greenhouse is well ventilated and yet you must still maintain the correct temperature.

Space is just as important as having enough air because your plants need lots of room for growth. So, when the leaves from two different plants start touching you should move them away from one another. Of course, this is easier if your plants are growing in pots.

Greenhouse Thermometer

Growing Temperatures

Once you have the right growing substances in place, you also need to think about the right growing conditions. This includes the growing temperature, and you also want to avoid sudden, extreme temperature changes. With this in mind, you'll need to watch out for those winter days where there's not a cloud in the sky so your greenhouse gets really warm. On these days you really need to ventilate your greenhouse, although the outdoor temperature may be at freezing or below. Then when you have a warm winter day you'll want to open all your windows, turn your exhaust fan on full (if you have one), and even keep the door ajar so you get plenty of ventilation. Ultimately, your goal is to keep your greenhouse thermometer between 45 and 50 degrees Fahrenheit during winter nights.

Plant Food and Water

Since you're not raising succulents or cacti, you want your plants to remain moist. However this doesn’t mean that it’s a good idea to maintain a regular watering schedule. This is because there are too many variables to cope with regularly. This includes things like the weather, how big of a pot your plant is in, and what type of plant you have. So, make sure you check the plant often and when the top of its soil is dry when you touch it, water your plant thoroughly. You'll find this isn't only easier, but your plants will grow bigger and better.

You also don't need to give any supplemental feedings to plants that are in good soil. When your already established plants experience weak or slow growth or have yellowing leaves, either the roots have filled up the pot or they're lacking some nutrients. If it's the nutrients your plant needs you'll want to give it a “spot of tea” in the morning on a sunny day.

To create the tea, fill a large pail with water and plenty of manure. Allow this to soak for several days, then pour it through a strainer into your watering can. Make sure it's the colour of weak tea. Don't feed this to your plants in extreme weather or when your plant is dormant or sick since this is akin to a big meal.


Most of the pests in your greenhouse are living out the rest of their life cycle. They're not really interested in your plants. So, while you'll see these pests around, you shouldn't see an infestation. If you do have one, simply move your plants somewhere so you can rinse the bugs off, then keep them isolated so you can watch over them. While this should take care of the problem, if it doesn’t, you'll need to throw your plants out. Make sure you don't do this anywhere near your greenhouse though or you risk extending the infestation.

Some of the types of pests you'll commonly see are:

  • White flies - these hate organically managed greenhouses.
  • Slugs – these seek out feeble plants. You should look in dingy areas for them and destroy them before they find their way to your plants.
  • Earwigs - these usually get trapped under things like rags.
  • Springtails – these are little hopping critters. They're harmless.
  • Mealybugs and scales – these are commonly found on woody plants (e.g. gardenias). If you don't bring these into your greenhouse you shouldn't have any issues with them.

Sow bugs, spider mites, and thirps - these only make their way into your greenhouse if you don't follow the rules. There's no way your greenhouse will ever be completely pest free since it's not a sterile habitat. It's both unreasonable and unnatural to even try to create this type of a greenhouse environment. As long as you take care of your plants' fundamental needs, you'll have the pests under control.

When you take the time to do these things, you'll go a long way in creating the perfect greenhouse for growing food. Relying on nature really will yield you a larger crop than you'd expect.