Boulders
Welsh slate and glacial stone boulders – a selection of large landscaping rocks for creating unique garden features.
Transform your garden or outdoor space with our natural stone boulders – carefully selected rocks of stunning Welsh slate and glacial stone. These are the perfect feature stones – 500 million year old pieces of history, yet suited to both traditional and modern garden designs.
These slate and stone garden boulders work well with our other stone products, and are often the focal point of a garden feature that includes our slate chippings and rockery stone.
Delivery included
Included in the price to most mainland England and Wales postcodes. Surcharges apply to London and Scotland.
Choose your delivery date
First available delivery is usually within 4 working days. Choose your date in your basket.
5 STAR REVIEWS
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QUALITY NATURAL STONE
Carefully sourced for landscaping projects across the UK.
What our customers say
From the quarry to your garden
★★★★★ 5.0 · Every review verified
Excellent service — delivery was very quick, and the quality and sizes of the slate were far superior to those of local garden centres. I would not hesitate to recommend Celtic Slate & Stone. A great supplier of natural British stone.
Very good quality stone, exactly as described on the website and nice big pieces, much better value than buying from the garden centre. Delivery was quick and exactly on schedule too. Thanks Steffan!
So pleased to have found Steffan at Celtic Slate & Stone — the only place willing to supply a smaller amount of rocks at a very fair price. Very helpful communication and a lovely selection of sizes. Very recommended.
We couldn't be more delighted with the flat pond edging stones we bought. They make the perfect lawn-to-border divide and surround to our pond project. They slot together in a suitably random but organised manner. We couldn't have asked for anything better.
Celtic Slate and Stone delivered an excellent product, amazing customer service and exactly what was promised. Steffan must have hand-picked many of the pieces of slate for my project. Unbelievable value for money.
Great product and service. I ordered a bulk bag of slate chippings for my garden. Lovely product, solid chunks of slate, unlike the flimsy small chips I've seen in neighbours' gardens. Delivered within a week.
Hand-selected slate and stone boulders, unique pieces from Snowdonia
The natural colour tones range from deep grey through to warm rustic and golden hues, with colours deepening and becoming more vivid when wet. As standalone feature stones, within garden rockeries, or around ponds and water features, slate and stone boulders have a character that imported or manufactured stone cannot match.
Every boulder on this page has its weight, approximate dimensions, and multiple photographs listed so you can make an informed choice. Stock changes as new pieces are selected, so if you see something you like it is worth ordering sooner rather than later.
What garden boulders are used for
Feature stones: a single well-chosen boulder placed within a planting scheme or at the centre of a garden design gives the garden a clear focal point. The natural character of each piece means no two gardens will look the same.
Garden rockeries: larger boulders used alongside our rockery stone create naturalistic rockery schemes with real scale and depth.
Pond and water feature surrounds: slate or stone boulders placed around, or even within ponds and water features complement the natural aesthetic of the water. Our boulders are completely non-toxic to fish and pond life and look great in contact with water as the colours are deepened and enhanced.
Landscaping and garden design: used by landscapers and garden designers across the UK to add natural structure, scale, and character to outdoor schemes of all sizes.
Delivery and handling
All boulders are delivered by pallet network on a large lorry with a tail lift and pallet pump truck. Delivery is kerbside or driveway where accessible. The pallet must be left on a level hard surface. Please ensure there is suitable lorry access at your delivery address before ordering.
Please note that the delivery company will not remove the boulder from the pallet, or assist in positioning it within your garden.
Many of our boulders are substantial in weight and may require mechanical lifting equipment to move from the delivery point. Weight is listed on each individual product page. Please plan for this before placing your order.
You choose your delivery date at checkout. The first available date is usually four working days from the date of order.
Frequently asked questions
Is each boulder listed individually?
Do the colours look different when wet?
Are the garden boulders safe for use in or around ponds?
Will I need equipment to move the boulder once delivered?
The delivery company will not remove the boulder from the pallet or assist in positioning it in your garden.