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The DIY Guide for Rooftop Gardening

If you live in a condo or don’t have a lot of outdoor space, building a rooftop garden is a great way to have regular contact with nature. A green roof is like a beautiful mini park with privileged views, flowers, shrubs, and vegetables. Having an urban rooftop garden is not only an easy way to beautify your home but you can actually produce fresh organic food and enjoy a quiet escape from the stress of everyday life. Plus, incorporating a green garden is a great way to create a new building amenity that is eco-friendly and promotes better living, sustainability, and socialization. 

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Practicalities to Consider

First you need to contact your home owner association or property manager and find out whether it is possible to create a rooftop garden. You don’t want to spend time and effort designing a garden only to find out you are not allowed to build one. If it is possible to convert your roof into a green space, then consult a contractor or architect and discuss whether your roof is strong enough to support the additional weight of a green garden. 

What You Need 

Pots 

Even if your roof is durable enough, you’d want to add as little weight as possible. You can use planting containers with lightweight potting soil to alleviate the weight on your roof. 

Choose pots that provide good drainage and are large enough for the plants you want to grow. Three-gallon pots are good for herbs such as dill, mint, parsley, and basil that grow well in a rooftop garden. Seven-to-five gallon containers are a good size for peppers while ten-gallon ones are great for eggplants and tomatoes. 

Pot material is also important. There is plenty of choice when it comes to pot material – metal, foam, fiberglass, glazed ceramic, plastic, and clay. Skip ceramic and terracotta, however, and opt for pots that are made of recycled materials or plastic. Ceramic and terracotta containers look beautiful but they tend to flake and crack due to changes in humidity and outside temperature. 

Soil

Since wet soil is heavy, you need lightweight potting soil for your garden roof. Opt for soil that is fluffy and light and provides moisture and air space.  Ideally, the growing media for your potted plants should also be stable, sturdy, and resistant to biodegradation and decomposition. Soil that is made of perlite, pine bark, and peat moss is a good choice for a growing medium as it ensures good nutrient and water retention. 

Also, consider things like the types of plants you want to grow, average low and high temperatures in the summer months, and average rainfall during the growing season. If you live in an area with low humidity, you would need soil that holds water while in places with a lot of rain and humidity, it is best to use soil that dries out fast. 

Plants to Grow 

Once the growing season begins, you will need seeds. Choose plants that are easy to grow in containers and will do well on an exposed sunny roof. Herbs such as mint, parsley, chive, and rosemary are some of the easiest plants to grow in containers. Other herbs for container gardening include lemon balm, Greek oregano, coriander, and sage. 

If you want to transform your rooftop into a beautiful garden, go for pansies, petunias, begonias, and roses. You can also grow exotic flowers like chenille plant, passion flower, and jasmine in warmer climates. 

And if you want to plant something that is edible, there are easy-growing options such as lettuce, tomatoes, peppers, peas, radishes, and beetroot. Easy container vegetables are also chilies, okra, eggplants, and onions. Keep in mind that eggplants, onions, carrots, and beets need more room while shallow-rooted vegetables such as cabbage, peppers, radishes, and lettuce will do well in a pot that is about 8 inches deep. 

There is also a virtually endless array of succulents and perennials to grow in your rooftop garden. Go for asters, daisies, ferns, and grasses as well as low-maintenance, waterwise plants such as aloes and cacti. You can also plant shrubs and dwarf trees such as lemon trees, crabapples, and Japanese maples but you will need bigger pots.

Final Words: Urban Gardening Matters

In addition to the virtually endless list of edibles, herbs, and flowers that you can grow, a rooftop garden offers some great ecological benefits. More green space means more oxygen and less air pollution. It also means more habitat and food for urban wildlife constantly adapting to an extreme city environment. Every inch re-greened boosts biodiversity, contributes to controlling urban temperatures, and makes cities more livable and sustainable. 


At John Mini, we’re not afraid to color outside the lines. Encouraged to think differently, our team takes chances, sourcing inspiration from unexpected places in order to always be at the forefront of landscaping trends.

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