Starting an Organic Rooftop Garden

If you’ve been gazing at the blank canvas that is your roof thinking it would be a great place to grow some all natural fruits, veggies, or herbs you’re not alone!  Urban organic gardening is becoming one of the fastest-growing trends – and rooftops are usually the best place to do it.

However, one can’t simply start laying down organic soil and call it a day.  There are a lot of factors to consider before beginning any rooftop garden project.  The more prep work and thinking you do ahead of time, the more likely you are to succeed!

5 Questions to Consider Before Starting an Organic Rooftop Garden

1 – Can I legally do it?

Do some research.  Laws on home gardening vary wildly.  Some cities discourage home gardens, others – like New York – actually offer tax rebates for rooftop gardens.  A call to your city hall should be one of your first steps. If you don’t own the property, make sure you obtain permission from the building or home owner.

2 – What weight can the roof support?

This is a major issue many people fail to consider.  Soil can be heavy, and wet soil and fertilizers are extremely weighty.  The underlying strata needed for drainage and support will add even more weight, along with the plants themselves.  Plus, there will be people tending the garden that will add additional weight to the roof as well. While weights will vary quite a bit, assume around 25 pounds per square foot for your rooftop garden, at a minimum.  You may want to contact an architect for a quick consultation before beginning the project, because this is one area you do not want to leave to chance.

3 – What are the sunlight conditions on the roof?

Study the way light hits the roof before deciding what plants to cultivate.  Are they going to be in direct sunlight all day?  Where will any shadows fall?  Are there any areas which won’t receive sunlight? One good technique is to video record your roof with time-lapse over the course of a full day.  Once you have the footage, it’ll be easy to see where the sunlight is falling, and at what times of day.  Based on that, you may want to invest in shades and think about the best placement to create optimal growing conditions.

4 – What will the winds be like?

Remember, rooftops – especially urban rooftops – get a lot of wind, far more than ground level.  Try and measure using wind meters beforehand. This will affect a lot of factors in your organic garden planning, including types of fruits, vegetables and plants, and how you manage necessary drainage. Using shutters to block, reduce, or redirect windflow is a viable option, but you need to know common wind patterns first.

5 – Is the roof sufficiently waterproofed?

If the roof hasn’t been thoroughly waterproofed beforehand, a rooftop garden can go wrong very quickly.  You will almost certainly want to purchase and install a waterproof membrane which will be at the bottom of your garden, protecting the roof.  If the roof is older or aging and known to leak, you’ll want to add waterproofing to the roof itself as well.

Starting your own rooftop urban garden can be highly rewarding. Research, planning, the right equipment, and fertilizers are key to creating a successful garden. Learn more about growing organic plants and produce, and find out how Organic Plant Magic Instant Compost Tea can help you fortify your fruits, vegetables, and flowers resulting in a lush, bountiful urban rooftop garden.