Silentnight Healthy Growth Astro Eco Comfort Pocket Kids Single Mattress
The Silentnight Healthy Growth Astro is a hybrid kids' mattress built around 600 Mirapocket® springs, which means your child gets support that adjusts to their body rather than a flat, one-note surface.
- Free from foam & chemical treatments
- Zoned springs that follow their shape
- 60-night trial & 5-year guarantee
£259
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Silentnight Healthy Growth Astro Eco Comfort Pocket Kids Mattress
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Mattress details
Mattress
Silentnight Healthy Growth Astro Eco Comfort Pocket Kids Mattress
Size
Firmness
Medium
Construction
Foam
Pocket Spring
Hybrid
Eco-Friendly
Depth (cm)
24
Layers
3
Layer Details
Sleep surface
A breathable quilted sleep surface, which means the top of the mattress lets air move through rather than trapping warmth. It's a simple layer doing a simple job.
Support system
600 Mirapocket® springs providing zoned support, which Silentnight says is scientifically proven to improve spinal alignment and posture. Each spring moves independently, so support follows your child's shape as they shift about.
Comfort layer
Breathable EcoComfort Fibres™ sit in the comfort layer for cooler sleep. This is where the mattress gets its softness without using any foam.
Layer details from silentnight.co.uk product page, September 2026.
Key benefits
- Fits a busy child's room: At 3ft wide the UK single leaves floor space free for a desk, wardrobe and toy storage, which matters when the bed is one item among many.
- Made for raised frames: The UK single is the standard fit for bunk beds, cabin beds and mid sleepers, though check your frame's maximum depth against this mattress's 23.5cm before buying.
- Works for shared rooms: Two UK singles plus a walkway fit in rooms where a bigger bed never could, so siblings sharing can each get proper pocket-sprung support.
- Cheap, easy bedding: Single sheets and duvets are the most widely stocked of any size, useful when a child gets through bedding faster than an adult does.
- Room to grow lengthways: At 190cm long, the UK single carries a child well into their teens, so the medium pocket-sprung support isn't outgrown after a couple of years.
This size suits you if...
You're buying for a child's bedroom, a bunk or mid-sleeper frame, or a compact room where the bed has to share space with a desk and wardrobe. It also suits a teenager moving up from a smaller children's bed, or a spare room that doubles as an office. Allow at least 2.1m x 2.8m of floor space and it fits comfortably.
Consider another size if...
Your teenager sprawls in their sleep or has clearly outgrown a 90cm width. We'd recommend the UK small double instead: it's 30cm wider, the same length, and needs a room of at least 2.4m x 2.8m.
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FAQ's
Will the Silentnight Healthy Growth Astro UK single fit a bunk bed?
Yes, the UK single is the standard bunk and mid-sleeper size at 90 x 190cm, and this is the size most parents buy for raised frames. One check first: this mattress is 23.5cm deep, so make sure the top bunk's safety rail still sits high enough above the mattress surface. Frame manufacturers state a maximum depth for exactly this reason.
What are the dimensions of the Silentnight Astro in a UK single?
The UK single measures 90 x 190cm, which is 3ft x 6ft 3in. It's the standard one-person size in the UK, so any single bed frame, divan or bunk sold here will take it. We suggest allowing at least 2.1m x 2.8m of floor space so there's room to move around the bed.
Is a UK single big enough for a teenager?
For most teenagers, yes. At 190cm long it's the same length as a UK double, so height is rarely the issue; width is what some teens outgrow. If yours is a restless sleeper who ends up sideways by morning, the UK small double gives 30cm more width at the same length, provided the room can take it.
How long will a child use a single mattress before sizing up?
Most children move onto a UK single at around the toddler-bed stage and stay on it into their late teens, so this is usually the last mattress size change until adulthood. That's worth bearing in mind here: the Astro's zoned pocket springs are aimed at growing bodies, and the UK single is the size that covers those growing years.
Can two of these singles work in a shared or guest room?
Yes, two UK singles side by side or on opposite walls is a common setup for siblings sharing or a guest room. Each mattress is 90cm wide, so measure your room with a walkway between the beds in mind. Two singles also let each sleeper have independent support, since pocket springs respond to each body separately.