Silentnight Healthy Growth Astro Eco 600 Pocket 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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Inside the Silentnight Healthy Growth Astro Eco 600 Pocket are 600 Mirapocket springs offering zoned support, which Silentnight states is scientifically proven to improve spinal alignment and posture, topped with breathable EcoComfort Fibres for cooler sleep. It's hypoallergenic and free from foam and FR chemical treatments, which will appeal if you're cautious about what your child sleeps on. At 23.5cm deep it's slightly shallower than a typical adult mattress, though that's normal for this type of design. Silentnight backs it with a 60-night trial and a 5-year guarantee.
Mattress specifications
Firmness
Medium
Type
Pocket Spring
Depth (cm)
24
Number of Layers
3
Trial Period (nights)
60
Warranty (years)
5
Price Range
£254 to £274
Best Sleeping Position(s)
Side Sleeping
Back Sleeping
Combination Sleeping
Certifications
Assessed from Silentnight's published specification for this mattress, captured September 2026, and from regular price comparison across our UK retail partners.
Why should you choose this mattress?
The main draw is the balance of support and breathability at a modest price. The 600 Mirapocket springs respond individually, which means the mattress adapts to a growing body rather than pushing back uniformly, and the zoned design targets spinal alignment. EcoComfort Fibres in the comfort layer help air move through, so warm sleepers should stay a little cooler through the night. There's no foam and no FR chemical treatment, a genuine plus for allergy-prone children, and the hypoallergenic build reinforces that. Yes, it costs more than a basic children's mattress, but the pocket spring construction and 5-year guarantee justify the step up. Delivery is quoted at 14 days.
Key features & 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.
Best suited for?
Children
Made as a children-focused design, its 600 Mirapocket springs move independently, so support adapts to a growing body rather than pushing back evenly.
Allergy sufferers
Hypoallergenic and free from foam and FR chemical treatments, it suits anyone wanting a cleaner, simpler build to sleep on.
Warm sleepers
Breathable EcoComfort Fibres in the comfort layer help air move through, which means you should stay a little cooler overnight.
Teenagers
Medium firmness with zoned pocket springs gives a balanced feel for growing bodies, and the Single and Small Double sizes suit a bedroom.
This is a children-focused design available only in UK Single and UK Small Double, so couples or anyone wanting a Double or larger should look elsewhere. If your child prefers a noticeably soft or firm feel, the medium tension may not suit. At 23.5cm deep, it's also slimmer than some adult mattresses.
Save on an earlier or ex-display model
Some retailers still sell the earlier version of this mattress, or ex-display and returned stock at a lower price. These are the sizes where it costs less than the current model's best price.
Silentnight Healthy Growth Astro Eco 600 Pocket Mattress
Last seen for £329 at Mattress Online on 25th June 2026
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FAQ's
How firm is the Silentnight Healthy Growth Astro Eco 600?
It's a medium feel, according to Silentnight. That middle-ground tension suits most growing sleepers in most positions, although children who strongly prefer a very soft or very firm surface may find it a compromise.
Does the Silentnight Astro Eco 600 come with a trial?
Yes. Silentnight offers a 60-night trial, so you can return it if it doesn't suit, and the mattress carries a 5-year guarantee.
Is the Silentnight Astro Eco 600 good for allergies?
It's certified hypoallergenic and is free from foam and FR chemical treatments, which makes it a sensible pick for allergy-prone children or parents who prefer to avoid chemical fire retardants.
What sizes does the Silentnight Astro Eco 600 come in?
Two sizes: UK Single and UK Small Double.
How deep is the Silentnight Astro Eco 600 mattress?
It measures 23.5cm deep. That's slightly shallower than many adult mattresses, but standard fitted sheets should still fit comfortably, and it's a sensible height for a child's bed frame or bunk.
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