How to Sow Annuals Directly into Your Garden Borders This Spring
After an unusually cool and dry April, many UK gardeners may feel a little behind with their sowing and planting. But don’t worry – May is the perfect time to catch up! One of the easiest and most rewarding ways to fill your garden with vibrant colour is by sowing hardy annuals directly into your borders.
Hardy annuals are a brilliant choice for adding quick, affordable colour to any outdoor space. They’re perfect for new gardens where you want fast impact while longer-term plants are still establishing, and they’re equally useful for filling gaps in existing borders.
In this guide, we’ll show you how to sow annuals directly into your garden soil – and suggest some essential products and trusted local garden centres where you can find everything you need!
Preparing Your Soil
Before you sow, you’ll need to prepare your soil properly. Start by breaking up the surface to create a fine tilth – a smooth, crumbly texture ideal for germination. Use a good-quality garden rake to remove any large stones and debris.
Pro tip: If you have time, create a 'stale seedbed'. Simply rake and water the soil, allow weeds to germinate naturally, then hoe them off using a sharp hoe. This helps eliminate weed competition before your precious seedlings emerge.
If you’re working with heavy or compacted soil, consider adding a thin layer of multi-purpose compost from trusted suppliers like Perrywood Garden Centre or Frosts Garden Centre – both renowned for their excellent compost selections.
In dry weather, water the entire bed thoroughly the day before sowing to encourage fast seed germination.
Sowing Your Seeds
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Rake and level the soil carefully. Adding a fine layer of compost makes this even easier.
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Mark out your rows using a sprinkle of dry sand – this helps you visualise spacing and can easily be adjusted.
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Create shallow drills (small trenches) about 15–20cm (6–8in) apart using a sturdy garden trowel. Alternating row directions across the bed prevents a rigid, striped look once your flowers bloom.
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Sow your seeds thinly along the drills, cover lightly with soil using your rake, and water gently but thoroughly. As your seedlings grow, thin them out carefully with a hand fork to allow space for healthy growth.
Top Annuals to Sow in May
Not sure what to sow? These hardy annuals are fantastic for UK gardens and available at most good garden centres such as Dobbies Garden Centres or Hillier Garden Centres:
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Nasturtiums: Edible, colourful, and easy to grow.
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Cosmos: Delicate, feathery foliage with big, bold blooms.
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Night-scented Stocks: Perfect for adding fragrance to evening gardens.
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Salvia viridis (Annual Clary Sage): Vibrant blue or purple spikes.
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Cornflowers: Classic cottage garden favourites.
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Cerinthe major 'Purpurascens': Stunning, bee-friendly blooms with dramatic purple foliage.
All of these can be sown directly into your prepared beds – you’ll find a brilliant selection of flower seeds at centres like Stewarts Garden Centre or Burford Garden Company, or even online via Duchy of Cornwall Nursery.
Must-Have Tools and Products
Before you get started, make sure you have the essentials:
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Garden Rake – to achieve a fine tilth.
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Hand Hoe – for preparing drills and weeding.
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Multi-Purpose Compost – for improving soil texture.
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Watering Can with Fine Rose – to avoid washing away tiny seeds.
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Quality Flower Seeds – from trusted UK garden centres.
Final Tip: Visit Your Local Garden Centre
If you're keen to see the best seasonal plants, seeds, and gardening tools up close, why not plan a visit to one of your local garden centres? Centres like Bents Garden & Home, Squires Garden Centres, and Dobbies offer fantastic seasonal ranges, plus expert advice if you need help choosing the right seeds and equipment.
Happy sowing – and here's to a beautiful, flower-filled summer ahead!
