DIY masterclass
Transform your garden by building a gorgeous, modern raised flowerbed – with a bit of planning it will only take a few days
Learn how to make your very own modern raised flowerbed for your garden
Raised beds are a great place to grow plants, improve soil conditions and can fill awkward spaces in the garden. Built from ground level up, you can create the conditions that ensure plants thrive, and you can custom build it to suit your own space. This one is made from ‘eco’ concrete blocks and is topped off with timber sleepers for extra seating – invaluable in a small garden.
With basic DIY skills, plus a spare weekend, you’ll soon have a raised bed that’ll provide a space for plants for years to come. Although the work itself doesn’t take more than two days, plan ahead as you’ll need to factor in two 24-hour drying periods.
1 Mark the bed shape by laying the blocks on the ground. Dig a shallow trench, 30cm wide and deep, for the foundation the blocks will sit on, and fill with a 20cm layer of rubble. Tamp down thoroughly with your heels.
2 Top up the foundation with a 10cm layer of postcrete and spread out using a shovel. Use a spirit level placed on a straight board to check the surface. When it’s roughly level, water the postcrete thoroughly.
3 Set the blocks on a bed of mortar. Start building at one corner of the foundations using mortar to stick the bricks together. Build the other corners level then the walls, checking they’re straight with a spirit level.
4 Once the blockwork has set (after 24 hours) make up the render (two parts sharp sand, two parts building sand, one part mortar). Add 600ml PVA adhesive per barrowful. This makes the mixture easier to work.
5 Wet the blocks using a watering can. This stops dry blocks from sucking the water out of the render. Apply 5-10mm of render using a plastering trowel. Keep wetting the blocks so the render goes on, and stays on, easily.
6 Once the render is fully dry (after a further 24 hours) make the edge with half sleepers. Secure them by screwing to off-cuts of sleeper inside the blockwork. Get someone to hold the off-cuts in place while you drill.
7 Paint the render using an exterior-grade masonry paint as this is the best type for using on rendered blockwork. One litre of paint will cover around six sq m of wall and you may need two coats for a neat finish.
8 Fill your new bed up with a soil/compost mixture such as blended loam or make your own mix using two-three parts garden soil, one part horticultural sand and one part well-rotted compost. Add more sand if you have clay soil. You’re ready to plant!