7 Step Soft Fruit Netting Build with Harrod Horticultural Cages Over a 6-Metre Bed

Mesh choice for raspberries and blackcurrants

Blackbirds and blue tits can get through 19mm netting in some seasons, so Harrod Horticultural sells two mesh grades for this type of cage: a 16mm woven butterfly net and a 19mm knitted bird net. For a 6-metre bed planted with raspberries and blackcurrants, the 19mm grade is the usual choice. It sheds rain more readily, and raspberry cane tips snag on it less during growth and picking.

The 16mm grade has a place where smaller gaps matter, though it changes the load on the frame. It is heavier, traps more leaf litter and loose plant debris, and on a long run that extra drag can pull the top sheet down between posts.

Do the netting calculation before ordering the frame covering. A 6-metre by 2-metre bed with a 2-metre cage height needs about 24 square metres of top netting, while the side sheets come to roughly 32 square metres before any overlaps are added. Harrod supplies netting in fixed widths, commonly 2m and 4m, so a single 4m-wide top run cut to 6.5m covers the span and leaves a 250mm drop on each side. If the layout allows one continuous length, use it. Each seam is another place a bird will test within a week of the fruit starting to colour.

Set out the post grid

Peg the four corners of the 6-metre bed, then stretch a builder’s line down both long sides. On the Harrod aluminium system, posts sit at 1.5-metre centres along the length. That gives five post positions on each side of a 6-metre run, ten upright positions in all, with the corner positions doing double duty for the side and end lines.

Mark every post position with a tape measure instead of pacing the bays. A small error repeated over five bays leaves one side sheet loose and the next one over-tight. Check the rectangle by measuring the diagonals: on a 6m by 2m bed, the diagonal is 6.32 metres by Pythagoras. If the two diagonal readings differ by more than about 30mm, shift one corner peg until they match. A cage built out of square fights the moulded top connectors, and a fitted door panel can bind in its frame.

Anchor the uprights in cultivated soil

Cultivated fruit beds are usually too soft to hold a bare 2-metre aluminium post upright for long. Pushed straight into dug loam, the post is likely to lean within a season. Harrod’s system has two footing options: a spiked socket for firm ground, and a bolt-down base plate for paving or decking. In a worked bed, the spike needs extra support.

Drive the socket against a timber offcut so the rim does not deform under the hammer. Refill around the socket with the soil that came out of the hole, tamping it in 100mm layers instead of dropping it back in loose. On very loose ground, set each corner socket in a 200mm concrete collar and leave the intermediate posts on spikes.

The corners carry the strain from side-net tension and the weight of the top sheet. When one corner leans, the ridge line drops and a triangular opening appears at the apex. That small gap is enough to undermine a neatly clipped side run.

Heavy clay brings a separate footing problem because it heaves in frost. In that soil, the bolt-down plate fixed to a buried paving slab performs better than a spike. Set the plate level with a spirit level across both axes before tightening the M8 bolts. One out-of-plumb post is enough to throw the whole bay out of line.

Build the top frame

Slide the horizontal eaves tubes into the corner and T-connectors at the top of each post. Harrod’s 25mm tube is a push fit into moulded nylon connectors, and the joint is held by friction plus a self-tapping screw through a pre-drilled hole. Work along one long side, then the other, then close the two ends.

A ridge tube down the centre line is optional on a 2-metre span and worth adding on wider cages because it stops the top net pooling water after heavy rain. With ten posts plus four corners, the top frame uses twelve eaves sections at 1.5m and two end sections at 2m. Tighten every connector screw before the netting goes on, since a loose joint that survives assembly can work free under wind load and netting drag inside a month.

Hang the top sheet and tighten the corners

Drape the top net over the ridge with the same overhang on both sides. Start at one corner and fasten the net to the eaves tube with the supplied plastic clips or 50mm cable ties at 300mm spacing. Pull each run tight along the tube before fixing the next clip, keeping the pull even along the length.

A loose top sheet soon forms bags between supports. Those low spots collect rain, and standing water stretches knitted mesh. In a hard frost, the same pooled water can freeze the net solid.

The ridge line needs enough tension to shed water, while the overhanging edges still need to meet the side sheets neatly at the eaves. If the top sheet is pulled hard in the middle and left loose at the edges, the side joint becomes awkward to close.

Leave the corners until the main runs are fixed. At each corner, the top sheet meets two side sheets. That three-way junction is a common probing point once raspberries ripen in July.

Fold the top net down over the corner connector and pin it until the triangular gap above the post cap has disappeared. Do the same at each corner, checking from outside the cage as well as inside it. Gaps around the cap can be hard to see from only one angle.

After clipping, run a hand along the ridge and feel for slack pockets. Any section that lifts more than 50mm off the tube under a light pull will sag further under its own weight and rainfall within weeks.

Knitted 19mm net stretches on the bias. A sheet that looks taut while dry will relax during the first wet spell, so re-tension the top clips once after the first rain. That later adjustment matters more than perfect first-day tension, because the mesh only settles after it has been wetted and pulled across the frame.

Close the sides and the soil seam

Most bird entry on a soft fruit cage happens at ground level. Blackbirds will walk under a side net that is pegged 100mm above the soil. Bring each side sheet down to the ground and hold it with a buried timber batten, a row of bricks, or earth staples at 400mm spacing. The aim is an unbroken seal where net meets soil around all four sides of the 6-metre bed.

Where two side sheets meet, overlap them by at least 150mm and clip the full overlap from the top edge to the soil line. At the eaves, overlap the side sheet with the top sheet and clip the two layers together. A butt joint leaves a slot along the frame.

If the Harrod zipped door panel is fitted at one end, check that the zip reaches the ground stop and that the flap below it pins flat. The bottom of the door is part of the ground seal, even when the rest of the panel looks square.

Check it again after seven days

After a week, walk the full perimeter slowly and look for movement caused by weather and handling. The ridge may have relaxed after rain, a side seam may have lifted off its pegs, or a corner fold may have opened under wind.

Pay close attention to the junctions that were tight on the day of assembly. Clips can hold the mesh while the mesh itself shifts around them. At the door end, the zipped panel is often the part that moves most because it is handled during picking. The zip can sit closed while the flap below it lifts, and that lower edge is hard to see from standing height.