Merino Wool Blanket and Throw Guide: Weights, Care, Comparisons

Wool blankets have been keeping people warm since before recorded history, and for most of that time nobody cared which sheep the wool came from. Then merino entered the conversation. Merino wool comes from Merino sheep, a breed developed in Spain during the Middle Ages and now raised primarily in Australia, New Zealand, and South America. What makes merino different from standard wool is the fibre diameter. Regular wool fibres range from 25 to 45 microns. Merino ranges from 15 to 21.5 microns, with superfine grades dropping below 17. That difference in thickness is the reason merino feels soft against skin while regular wool makes you itch.

Why Microns Matter More Than Marketing

The softness of any wool product depends almost entirely on fibre diameter, measured in microns. Below 20 microns, most people cannot feel the individual fibres against their skin. Above 25, the fibres are stiff enough to trigger the itch response in nerve endings. This is not an opinion. It is a measurable physical property that explains why your grandmother's wool blanket was a torture device while a merino throw feels like wearing a cloud.

Superfine merino (15-18.5 microns) approaches cashmere territory for softness. Ultrafine merino below 15 microns is rarer and costs accordingly, but it exists for people who want the temperature regulation of wool with the hand feel of silk. Standard merino at 19-21.5 microns is the most common grade used in blankets and throws, and it is soft enough for most people to sleep under directly without a cover between the wool and their skin.

The micron count should appear on the product label or listing. If it does not, the manufacturer is either using a blend of merino grades or mixing merino with standard wool and hoping you will not notice. A blanket labelled "merino blend" can contain as little as 20% merino with the balance being coarser, cheaper wool. Ask for the micron count before buying. If the seller cannot provide it, that tells you something about what you are getting.

Merino vs Lambswool vs Cashmere

Lambswool comes from the first shearing of any sheep breed, typically at around seven months. It is softer than adult wool from the same breed because the fibre tips have never been cut, creating a natural taper. The micron count varies widely depending on the breed, usually falling between 20 and 28 microns. Lambswool blankets are warmer than merino in raw insulation because the fibres tend to be thicker and trap more air, but they do not breathe as well. For a bedroom blanket, this means lambswool may cause overheating in warmer months while merino adjusts.

Cashmere comes from cashmere goats, not sheep, and the fibres are finer (15-18 microns for quality grades). Cashmere can be seven to eight times warmer than merino by weight, which sounds appealing until you realise that a cashmere blanket in a heated Canadian bedroom can cause overheating. Cashmere also lacks the lanolin and antibacterial properties of merino, pills more aggressively with use, and costs substantially more. A merino wool throw runs $150-$300. A comparable cashmere throw starts around $400 and climbs quickly.

For year-round bedroom use in Southern Ontario, merino hits the practical sweet spot. It insulates enough for November nights without suffocating you in July. Lambswool works better as a dedicated winter blanket. Cashmere works best as a living room throw where it sees less nightly body heat and moisture.

Weights, Weaves, and Choosing the Right Throw

Merino blankets come in several weight categories that determine how they feel and when to use them.

Lightweight throws (200-350 GSM) work as layering pieces on beds and as standalone wraps on the couch during milder weather. They drape beautifully, fold compactly, and travel well. Most "wool throws" in this category weigh under two pounds and measure around 50 x 70 inches, large enough for one person but too narrow for a shared bed.

Medium-weight blankets (350-500 GSM) serve as primary bed blankets during shoulder seasons, spring and fall, when a heavy duvet is too much but a sheet alone is not enough. These are the most versatile weight for year-round use in heated homes. Paired with a lightweight duvet in winter, they create a layered system that adjusts to temperature swings overnight.

Heavy blankets (500+ GSM) function as winter bedding on their own or as substantial throws. They are warmer but bulkier, harder to wash at home, and more expensive. If you sleep in a cold room or keep the thermostat low overnight, a heavy merino blanket can replace a duvet entirely.

Weave matters too. A woven merino blanket has a tighter structure that resists pilling and holds its shape over years. A knitted merino throw is softer and more flexible but stretches over time and pills faster. Herringbone and twill weaves are the most common for woven merino blankets, offering a balance of visual interest, durability, and drape.

Frequently Asked Questions