Silentnight Healthy Growth Astro Eco 600 Pocket Single Mattress
The Silentnight Healthy Growth Astro Eco 600 Pocket is a medium-feel pocket spring mattress designed for growing sleepers, available in UK Single and UK Small Double.
- Support that adapts as they grow
- Breathable fibres help kids sleep cooler
- 60-night trial & 5-year guarantee
£254
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Silentnight Healthy Growth Astro Eco 600 Pocket Mattress
More available sizes
Last seen for £329 at Mattress Online on 25th June 2026
Mattress details
Mattress
Silentnight Healthy Growth Astro Eco 600 Pocket Mattress
Size
Firmness
Medium
Construction
Pocket Spring
Eco-Friendly
Depth (cm)
24
Layers
3
Layer Details
Sleep surface
A breathable quilted sleep surface, which means a soft first point of contact that lets air circulate rather than trapping warmth.
Support system
600 Mirapocket springs providing zoned support, which Silentnight states is scientifically proven to improve spinal alignment and posture. Each spring moves independently, so support follows the body's shape.
Comfort layer
Breathable EcoComfort Fibres designed for cooler sleep, helpful if your child tends to overheat at night.
Layer details from silentnight.co.uk product page, September 2026.
Key benefits
- Fits the smallest bedrooms: At 90cm wide it needs only 2.1m x 2.8m of floor space by our guidance, so a bed, wardrobe and desk can coexist without a squeeze.
- Suits raised frames: At 23.5cm deep it sits below the safety rail height most bunk, cabin and mid sleeper frames require, where a taller adult mattress would not.
- Grows with your child: The 600 Mirapocket springs respond individually, which means support keeps following a growing body rather than pushing back in one uniform block.
- Works for sibling rooms: Two UK singles plus a walkway is manageable in a shared room where anything wider would swallow the floor.
- Cheap, easy bedding: Single sheets and duvets are the most widely stocked of any size, useful when a child gets through bedding quickly.
- Cooler for restless sleepers: The breathable EcoComfort Fibres let air move through the comfort layer, helpful for children who run warm at night.
This size suits you if...
You're buying for a child or teenager and want a supportive step up from a basic foam mattress, your room needs to fit a bed alongside toy storage, a desk or a second bed, or you need a mattress shallow enough for a bunk or mid sleeper. It also suits a spare room that doubles as an office, where a 90cm footprint keeps the space usable by day.
Consider another size if...
You're buying for a teenager who sprawls, or a solo adult who wants extra width to spread out. This mattress also comes as a UK small double, 30cm wider at the same length; we'd suggest allowing at least 2.4m x 2.8m of floor space for it.
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FAQ's
Is the Silentnight Astro Eco 600 single suitable for a bunk bed?
Generally, yes. At 23.5cm deep it's slimmer than a typical adult mattress, which works in its favour on raised frames where the mattress must sit below the safety rail. Check your frame's stated maximum mattress depth before buying, as this varies between bunk, cabin and mid sleeper designs, but most accept this depth comfortably.
What room size do I need for the Astro Eco 600 in a UK single?
We suggest allowing at least 2.1m x 2.8m of floor space. That leaves room to walk alongside the bed and open drawers or wardrobe doors. In a loft conversion, the 90cm width also makes it easier to tuck the bed under the slope while keeping standing height where you actually need it.
How long will a UK single last a growing child?
At 190cm long, a UK single is the same length as a UK double, so most children won't outgrow it lengthways even as teenagers. Width is the more likely reason to size up. The zoned Mirapocket springs are designed around spinal alignment for growing sleepers, which suits this stage well.
Should I get the single or small double Astro Eco 600?
The UK single is 30cm narrower than the UK small double and the two are the same length. For a child's room sharing space with storage and a desk, or for bunk frames, the UK single is the practical pick. If the room allows 2.4m x 2.8m and your child is heading into their teens, the UK small double gives welcome extra width.
Can an adult sleep on the Astro Eco 600 single?
A UK single is the standard one-person size, so it works for a single adult or occasional guest use, and the medium feel suits most sleepers. Bear in mind the design is aimed at children and, at 23.5cm, it's slightly shallower than many adult mattresses, so heavier adults may prefer something more substantial.