If you are looking at two bags of hard-wearing seed and wondering which will make the better lawn, start with what you want the space to do. A family lawn you enjoy looking out onto and a heavily used area you mainly want back under grass can lead you towards different choices.
I have used HM3 on a worn part of my lawn and liked the denser result once the ground was prepared and the seed kept damp. It is the one I would look at first for a family lawn where appearance matters as well as everyday use. I would also consider HM4 for straightforward, hard-wearing repairs, especially where practical grass cover is the main aim.
Both need the right conditions. Here is how I would make the choice before worrying about bag size.
I personally use Hurrells seed for most lawn work — it’s consistent, reliable, and suited to UK conditions.
👉 Use promo code FORMBY10 for 10% off at Hurrells Seeds
Alternatively, if you prefer to buy through Amazon, you can view available options here:
👉 Visit the Hurrells Seeds Amazon Store
Think about the lawn you will maintain
The seed has to suit the lawn after it germinates. Think about how often you mow, how the space is used and whether you can keep it watered while it establishes. A mix chosen for a fine-looking lawn will not deliver that appearance if the grass is continually scalped or the repair is walked over straight away.
HM3 contains a broader combination of grasses; HM4 has a simpler ryegrass-and-fescue blend. The composition table below shows the difference, but percentages alone do not settle every garden. Shade, drainage and persistent wear may matter more.
For a repair, consider how the new patch will sit beside the existing lawn. Fresh growth can look different at first, and another mixture may have a different texture. If you are improving a whole thin lawn, even overseeding can make more sense than choosing a different bag for every spot. Keep a record of what you sow for future repairs.
Once you have chosen, measure the area and buy for the job. Pack coverage is not a reason to spread the whole bag, and a larger bag will not rescue a seedbed that dries out.
What is in each bag?
According to Hurrells, HM3 contains 30% dwarf perennial ryegrass, 30% strong creeping red fescue, 10% slender creeping red fescue, 20% Chewings fescue, 5% smooth-stalked meadow grass and 5% browntop bent. That totals 60% fescues alongside 10% other species. HM4 is simpler: 50% dwarf perennial ryegrass and 50% strong creeping red fescue.
Those percentages tell you more than a “hard-wearing” label. HM4 has a larger ryegrass share and Hurrells calls it the faster-establishing, toughest amenity option. HM3 has a wider mix and is described for an attractive hard-wearing front or back lawn, including foot and pet use. That does not make HM3 a shade mix or mean HM4 will overcome deep shade or persistent waterlogging.
| Mix | Dwarf perennial ryegrass | Fescues | Other grasses |
|---|---|---|---|
| HM3 | 30% | 60% | 10% |
| HM4 | 50% | 50% | None listed |
Choose for the real use of the space
For a busy, reasonably open area, the result I had with HM3 makes it a practical family-lawn choice. I still prepare the seedbed, water and ease off heavy use while new grass establishes; a bag cannot do that work for you.
On a back lawn that receives regular family traffic but is also seen from the house, HM3 is the more appearance-led option. It is the choice when you will prepare a proper seedbed, keep people off while the new grass establishes and maintain the result. On a utility area with persistent wear, HM4 puts more weight on quick establishment and repair.
If the site is mainly dry, sandy and exposed, first consider whether either general lawn mix is the right category. Our sandy-soil grass seed guide deals with that constraint. Likewise, our shade seed guide addresses a different problem. Changing from HM3 to HM4 will not add sunlight or improve drainage.
How much to order
Hurrells states the same 5 kg coverage for both mixes: 140 m² when sowing a new lawn and 200 m² for overseeding. Its 10 kg figures are 280 m² new and 400 m² overseeding. Choose the rate that matches the job. Replacing an entirely bare surface with a thin overseeding dose leaves too little seed for the intended coverage.
Measure the grass area, then round up to an available pack size. For an 85 m² new lawn, one 5 kg pack is sufficient on the manufacturer’s coverage figure because 5 kg covers 140 m². For 230 m² of overseeding, a 5 kg pack would be short of the stated 200 m² coverage; consider the next suitable pack size. See our quantity and pack-size guide for the arithmetic.
The RHS advises repairing bare patches in spring or autumn and following the seed packet rate; its general patch guidance is not a substitute for the chosen Hurrells product instructions. Both HM3 and HM4 specify a fine, firm seedbed and soil temperatures of at least 10°C for germination. Sowing into compacted rubble or very cold ground and then comparing brands will not reveal the mix’s potential.
Final buying check
Read the live composition and coverage before ordering, especially if buying a different pack or future season’s supply. Choose HM3 here when a fine-looking, durable family lawn is the aim; choose HM4 here for straightforward utility and faster recovery. Prepare, water and protect the seed properly whichever you buy.
Sources and specification checks
Manufacturer specifications checked 19 September 2026. Check current retailer variant and terms. Featured image is an AI-generated illustrative scene, not a product test photograph; supporting graphics are original.
