You've got a roof that's ripe for the planting, and you can't wait to start a rooftop garden. You envision an oasis where you can spend summer days away from the swelter of the pavement. You want to create a habitat for birds and insects and bring some beauty to your concrete environment. But you've heard rooftop gardens can be challenging. What are the most common problems with rooftop gardens? We researched this topic to get you all the answered you need!
Rooftop gardens are both beautiful and occasionally challenging. Here are the common problems a gardener may have with a rooftop garden.
- Accessibility to water and drainage issues
- A way to bring gardening supplies to the roof
- More extreme weather exposure to your plants
- Structural issues with the roof
We'll look at these points in more detail below, but know that a rooftop garden can be rewarding and worth figuring out how to grow.
The Ins And Outs Of Rooftop Gardens
Having a rooftop garden gives you a whole new perspective on the world below. The sound of the city street becomes background noise when you watch butterflies enjoy your blooms. Vegetables, flowers, climbing vines, even trees are possible to grow you the roof. But do you have everything you need for that rooftop garden?
Accessibility To Water
Rooftop plants need plenty of water. You will plant them in containers, and container plants require more frequent watering than those planted in-ground. Plus, wind, sun, and rain will buffet your plants a little harder on a rooftop than on the ground, or sheltered on a patio or porch. So you need easy access to water. Is there a spigot on your roof? Is it close enough to your garden area?
Recoil garden hoses don't take up much space and come in a variety of lengths to reach your planters from your spigot. This model also comes with a sprayer jet.
Even with containers, you need to watch out for the effects of drainage on your roof. Make sure you have pot saucers for your containers, or otherwise protect the area underneath the containers from drained water.
What if you don't have water? You have two options. Haul the water up to the roof by the watering can full or install a rain catchment system. Rain barrels are readily available and come with spigots to which you can attach a hose. They are often connected to a downspout, but you can also use them to catch the rain from the sky.
Hauling Supplies To The Roof
Getting a rooftop garden installed can cost a lot of time and labor, depending on how tall your building is. In some cities, like Boston, that have three or four-story brownstones, there are companies you can hire with cranes to help you get large plants, planters, and materials up top. This can be costly, so it's best to go in with your entire garden plan laid out so you can do it in one fell swoop.
For the hobby gardener, you should probably start small and let your plants grow big. Many planters and shelving units and trellises can be assembled after arrival, and thus will be easier to get to the roof. Start with smaller plants rather than trying to haul up mature specimens.
Besides water, you need a place for your gardening tools, extra soil and fertilizer, and perhaps an umbrella for your garden table.
This weatherproof bench provides 70 gallons of storage capacity underneath the seat and is a beautiful place to rest and enjoy your plants. It will arrive unassembled, so it is easier to get to the roof than a fully assembled piece. It weighs only 35 lbs, but can hold up to 770 pounds and is lockable with a padlock. It is available in three colors.
If you need something vertical for taller tools and a patio umbrella, there are great garden cabinets available. This one is weatherproof and engineered for strength and stability, but keep in mind that you may need to secure it further on a roof. It can be locked with a padlock. It's easily assembled but weighs 61 lbs, so it may require some help to get it up to the roof.
More Extreme Exposure For Your Plants
On the roof, there is little protection for your plants from the elements. If you have a low wall, that can help protect shorter plants from harsh wind, but taller plants may need to be staked to withstand breezy days. The sun can be brutal on the roof, and with plants in containers, so you'll need to make sure they have plenty of water. Plant things that can handle the heat and sunlight.
If your idea of a rooftop garden is to be your oasis, consider that you'll be more visible to the world. You may consider erecting trellises and growing a privacy screen of vines or flowering plants.
Bamboo planted in low pots can make a gorgeous privacy screen. Hardy in zones 7-11, it does well in full sun or partial shade and can get as high as 25' tall if you let it.
Large rectangular planters like this will work well along your wall that needs privacy.
Structural Concerns And Permissions
If you don't own your building, you must check in with the powers that be to make sure you have permission to start your rooftop garden. Once permission is granted, then you'll need to find out the load capacity for your roof. Soil is heavy, and it can be tempting to add more and more. If you live in a snowy climate, don't forget to add that weight plus your soil weight (unless you plan to empty all your pots in the cold season) into your calculations.
Rooftop Garden Versus Green Roof Garden
What about making your roof a living, breathing thing? That too is possible, but it's a whole different sort of roof garden. In Europe, there are companies dedicated to turning your roof into a living organism. There are advantages and disadvantages to this type of garden as well, but that's for another post.
If you want to learn more about gardening in containers, please check out these other posts at GardenTabs.com below: