Netting can keep birds off berries, stop insects reaching brassicas and give climbing plants something to hold. This garden netting calculator works out how much you need. Choose whether you are covering a bed or cage, or building a vertical trellis, enter the dimensions and an allowance for overlap, and it returns the area in square feet and the sizes to look for.
How to use the garden netting calculator
- Pick the use. A cover goes over the top and down all four sides of a frame. A trellis net hangs vertically between posts.
- Enter the length, width and height in feet. Width is not needed for a trellis.
- Set an allowance. Ten percent is a good start for overlap, trimming and tying down edges.
- Read the total. For covers, it also shows the size of a flat sheet that folds over the top.
How the area is calculated
For a cover, the area is the top (length times width) plus two long sides (length times height) plus two ends (width times height). For a trellis, it is simply length times height. The allowance then increases the total, because netting is sold in fixed sizes and you will lose some to overlaps and cuts.
Choosing the right netting
| Purpose | Look for | Notes |
|---|---|---|
| Bird protection for fruit | Small-mesh netting held clear of the plants | Birds can peck through netting that rests on fruit |
| Insect protection | Fine insect mesh | Seal edges fully, and cover plants before pests arrive |
| Climbing support | Strong trellis netting or mesh | Match strength to the weight of the crop |
Using netting safely and well
- Keep it taut and supported. Loose, sagging netting can entangle birds, snakes and other wildlife. Use small mesh, keep the net tight, and check it often.
- Support it on a frame of posts, hoops or a cage so it does not rest on plants. For hoop-style covers, the row cover fabric calculator uses the same idea.
- Plan posts and wire for a trellis with the trellis post and wire calculator.
- Leave access. Fit a zipped or clipped opening so you can reach plants, and remove covers from flowering crops that need pollinators.
- Take it down after the season, clean it and store it out of the sun, so it lasts longer.
Limits of this tool
These are estimates for plain rectangular frames. Curved or sloped structures need different shapes, and netting sizes vary by maker. Add extra if you are unsure, and follow the manufacturer’s advice for the product you buy.
Frequently asked questions
How much netting do I need for a 4 by 8 foot bed?
For a frame 4 feet tall, about 141 square feet with a 10 percent allowance. Enter your own dimensions above for exact numbers.
Is garden netting safe for wildlife?
It can be if kept tight and supported. Loose netting can trap birds and snakes, so use small mesh, keep it taut and check it regularly.
What size mesh should I use?
Small enough to keep out your target pests: fine mesh for insects, small-hole netting for birds. Packaging usually states the use.
Can netting rest directly on plants?
It is better to hold it clear of the plants on a frame, since birds can peck fruit through net that touches it.
How long does garden netting last?
Several seasons if you take it down, clean it and store it out of the sun.