Let’s face it, we’d all love a beautiful garden at home, especially in the summer months. However, with over 90% of the UK population set to live in built up cities by 2030, (source) keeping your green thumbs green, isn’t always that easy. That’s why roof gardens are so popular when you simply don’t have the outdoor space.
Roof gardens are a great way to create a little haven in the bustling city, that are great for attracting wildlife too. However, as Roof Maker explains, it’s important to consider a few factors if you want your garden to thrive, a few stories high…
1. Planning to plant
Before you start selecting your soil and collecting your compost, it’s important to check your property can safely handle the extra weight you’ll be putting on it. To be sure, contact a structural engineer who can tell you if this is the case.
You could consider installing walk on glass roof lights to your new rooftop garden. These roof lights are made from reinforced glass, so they can take the weight, while they also add wow-factor to your rooftop haven.
Finally, contact an expert to make sure you’re not breaching any building regulations and ensure you have sufficient drainage and access to a good water source too.
2. Containers vs the elements
Your rooftop garden will obviously be exposed to all sorts of weather, so it’s important you choose containers that won’t topple easily. Be sure to choose pots and containers that are low and wide rather than tall and thin. Try protecting against wind the natural way by planting windbreak plants like climbers or waxy cuticles too.
It’s important to consider that wind and sun exposure on roofs means plants will lose moisture a lot quicker too. Therefore, choose non-porous materials like metal or plastic for your containers, instead of terracotta which loses moisture.
3. A question of compost
Roof garden plants will have much less access to nutrients compared to traditional garden plants, so what compost you use is vital. Try mixing materials like perlite into your compost which will help your plants retain moisture and nutrients. It’s also important to choose a lightweight soil. Remember, there is soil you can buy specifically for rooftop gardens.
4. What grows well?
It’s important to consider plants and vegetation that naturally thrive in sunny and windy conditions for your roof garden. There a wide selection of plants that are very suited to mountain or coastal areas, which are a great place to start.
If you’re going organic, there are also several vegetables that grow well on rooftops. Lettuce, cucumber, spinach, and kale are all good choices and will be on your dinner plate in no time.
Yes, flowers require a lot more maintenance than other plants but their colour impact makes it all worthwhile. Choose Gazanias or “the African Daisy” which come in a variety of stunning colours and only need watering occasionally.
Swiss trailing geraniums are a popular choice, with their vivid colours and again only require watering and occasional pruning of wilted flowers.
Prefer the look of wild flowers? Aster Alpinus is a popular choice that will also attract butterflies to your roof garden while Yarrow, another wild flower, is a great choice for roof gardens due to its robust nature.
6. Going green
Ornamental grasses will add drama to your garden, even on the roof! Juniper and Phlomis are common at higher altitudes, such as hill sides, which makes them perfect for your rooftop too.
Succulents are also a trendy choice right now but have always been a staple ingredient for roof gardens. Try Stonecrop, which is a hugely popular succulent and comes in a variety of colours.
7. Add some fragrance
Again, choose fragrant flowers that can withstand sharp temperature changes for your roof garden. The Rock Rose or Cistus, is a colour and aromatic plant that blossoms in sunny weather but can also withstand below freezing temperatures as well.
Rosemary and thyme also smell great and do well in sunny, dry and windy conditions while Oregano is another fragrant choice. All will go well on the dinner table too!