Green manure UK allotment: clover before the crop

The bed is empty after the potatoes, the neighbours are sowing clover, and the packet in your hand might be a lawn mix. Green manure UK allotment covers are a crop you grow in order to cut. The Royal Horticultural Society distinguishes a red clover you can leave for one to two years from crimson clover that stops when you cut it to the ground. A micro-clover lawn packet is a third plant. The vegetable that follows, cucumbers included, keeps its own sowing date.

In short

Sow a green manure between March and August, on an empty bed, and choose the clover by how it ends. Essex red clover can occupy the ground for one to two years. Crimson clover does not regrow after a cut to the ground. White and micro clover are lawn plants that persist under mowing. Clear the cover in time for the next crop’s own calendar. This page states no nitrogen figure.

A cover is not a lawn

A lawn clover is sown to stay, and you mow it. A cover is sown to occupy bare soil and then give the bed back. The RHS green-manure notes put sowing in March to August. That is a wide window. It is not permission to scratch seed into a standing crop, and it is not the same rate as overseeding a turf. Bare or cleared ground, a rake, and seed in contact with damp soil are the start. Birds and a dry week still apply, as they do to any small seed.

White clover, Trifolium repens, is the low lawn species. Red clover, Trifolium pratense, is the taller meadow plant on the RHS clover-in-lawns page. Crimson clover, Trifolium incarnatum, is the upright annual cover. If the title says clover and the Latin name is missing, you do not yet know which job you bought. Our clover seeds comparison holds those packets. The top listing is Pronto Seed white clover, 2 kg at about £62.98, rated 4.4 from 159. The file calls it the large-lawn option, and also straight white clover for a big green-manure area. Two kilograms is a lot for one allotment bed, and it is white clover, not crimson.

A ten-species pouch that includes buckwheat and sainfoin as well as clovers is a cover blend, not a lawn and not a wildflower specification. Sow it only if you want every species on the list, including those that set seed if you leave them. Emptying a cheap micro-clover lawn packet onto a veg bed is how white clover becomes a weed in the carrots.

Red and crimson on the RHS calendar

Essex red clover, on the RHS green-manure page, is the long cover: one to two years. That suits a bed you can spare, a new plot, or a planned rotation gap. It does not suit the square you need for cucumbers in May. Turning a young stand in April is a shorter use than that note, and only if the plants will still turn in and the next sowing date is safe. Letting red clover flower and seed on a small plot builds a weed bank.

Crimson clover is the cover that finishes. The RHS says that once you cut it to the ground it does not regrow, and the plant page calls it an upright cover. Sow in the March-to-August window, let it leaf, and cut it when you need the ground. Topping it at 15 cm leaves a crown that can try again. Cut to the ground when you mean to end it.

A late August crimson sowing may be small going into winter, and a hard site can knock it back. This article will not invent a survival temperature. If the bed must be workable for an early spring crop, finish the cover in autumn, or accept that a winter-standing clover has to be cut before the seedbed. Red clover left for one to two years is still there in January. Do not sow it on a bed you wanted in March.

Acid, waterlogged ground is a poor clover site. The RHS white-clover page says waterlogged or very acid places suit it poorly. A green manure that sits yellow in a puddle is the drainage, not a failed variety. Raise the bed or sow something the wet spot can actually carry. Resowing clover into the same puddle repeats the yellow patch.

Cutting and the next sowing

Cut or dig while the cover is still leafy, and before it sheds seed. The finishing cut on crimson is to the ground. Then rake a bed you can sow or plant. Thick green material dug in on the morning you sow can leave hollow, airy soil that small seeds dislike. The RHS notes we used do not give one waiting period for every soil. They do give the next crop its own calendar.

Cucumbers follow the RHS cucumber page, not the green-manure page: heated sowings from mid-February to mid-March, unheated cover in April, and outdoor routes later. Waist-high crimson on the outdoor bed in late May is a cover in the way of the direct-sowing window. Cut it in time to make the seedbed, or sow in pots and plant when the bed is clear. Our cucumber seeds comparison is the variety list. It does not include a manure. A lawn clover under the cucumbers is a perennial left in the row.

This article gives no nitrogen figure in grams. A marketplace bullet that states a fertiliser value is a claim on that packet, not a result we measured. A sparse, droughted clover adds less bulk than a dense one. What you can see is cover versus bare soil, and a bed you can get back.

Water the cover in a dry spring so it establishes, then stop feeding it like a lawn. A fed, mown micro clover is turf. A cover you mean to finish by cutting should not be trained to survive mowing. Extra cuts that stop crimson seeding are management. The finishing cut is to the ground.

Packets in the clover comparison

Pronto’s 2 kg white clover leads the comparison on stars and review volume: 4.4 from 159, at about £62.98. The coverage line is up to 100 square metres per 1 kg, a lawn-scale claim, and far more seed than a 10 square metre trial needs. The species is still white clover. Damavand red clover is about 10 g and 3,000 seeds at about £2.99, rated 4.2 from 228, with a height line of 15–60 cm. That is meadow and cover height, not a micro lawn. Just Seed wild white clover prints Defra 7291 and organic registration AP23164. Those are registrations on the listing, not a CS certified-seed label, and we do not say the packet complies with the seed rules.

Buy the species you can finish. Crimson, if the packet is truly Trifolium incarnatum, matches the cut that does not regrow. Red clover matches a plot you can rest for one to two years. White and micro clover match a lawn you mow. Check the physical packet when it arrives. Titles drift.

A qualifying purchase through our link can earn a commission at no extra cost to you. Prices are captured amazon.co.uk figures in GBP and will move. We read the RHS pages and the listings. We did not weigh foliage or test nitrogen.

Rhubarb and mushrooms are other products

Rhubarb is a crown you plant and crop for years, not a seed cover you cut in before a salad bed. The rhubarb plant comparison lists crowns such as Timperley Early and Victoria. Clover in a rhubarb bed competes with a perennial you meant to keep. If that ground is for rhubarb, plant the crown and keep the clover for another plot.

A shiitake kit is a culture, often indoors on a block, not an allotment cover. The mushroom culture comparison is that shelf. Green manure is seed on empty soil, cut before the next sowing. A kit or a crown does not follow the clover calendar.