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Harvest seeds or take green hay to restore other grassland sites
The guidance on this page is for SFI pilot participants only. Please visit GOV.UK for the official Sustainable Farming Incentive scheme guidance.
Find out how land managers can take green hay and harvest seeds to help create or restore species-rich grassland.
If you’re completing this action as part of the Sustainable Farming Incentive pilot, how you do it is up to you.
The advice on this page can help you get better environmental and business benefits, but you do not have to follow it to get paid.
Seed harvesting and green hay
You can use seed and green hay from a donor site to create or restore species-rich grassland.
Green hay is made up of wildflowers and grasses that are harvested just as they are shedding seed. It’s cut and collected from the donor site before it dries. Once spread on the recipient site the seed drops out of the hay and germinates.
Why harvest seed or take green hay
These methods use local seed which:
- is suited to local soils and climate
- conserves the species and character of local grasslands
Spreading species-rich green hay can be an effective way to restore grasslands. Green hay is better than dry hay because more wildflower seed remains in the flower heads.
Choose a green hay donor site
Possible donor sites include meadows, banks and road verges.
Choose a donor site which:
- is close to the recipient site, as you need to spread seed within a few hours of collection
- has similar characteristics to the recipient site including soil type, soil pH and how wet it is
- allows you to physically cut and collect the vegetation, for example by avoiding unsuitable steep banks
- has not been a donor site in the past 2 years, to make sure there’s not too much seed taken from one site
- is big enough to supply the recipient site, for example green hay from 1 hectare should be enough to spread on 3 hectares
The sward should:
- support a range of target species that are absent or scarce on the recipient site
- be free from injurious weeds, like spear thistle, ragwort and broad-leaved dock
- have few or no competitive species like white clover and creeping buttercup, as they will compete with wildflowers
Be careful to avoid damage to nesting birds, invertebrates and plants of interest on donor sites, particularly on sites that are not normally managed by cutting.
How to take green hay
Leave the sward uncut and ungrazed for 2 to 3 months before you cut green hay. This will allow the plants to flower and set seed.
It’s best to harvest, collect, transport and spread the hay within an hour. Make sure you do it within half a day at most and the cut hay is not wilted or turned. Once cut and gathered, green hay heats up very quickly, which can make the seeds infertile.
To make sure there is enough seed left to maintain the donor site, consider harvesting just part of the site (for example, harvest a strip, then miss a strip).
You can:
- use a forage harvester to collect the hay in a trailer or muck spreader
- spread hay with a muck spreader
- bale with a round baler into loose, netted or tied bales
- spread bales using a haybob or tedder, straw chopper or muck spreader
- use a fork for small areas to collect and spread by hand
Spread hay as thinly and evenly as possible to avoid creating a mulch which can stop seeds germinating.
When to take green hay
Cut green hay when most wildflowers are seeding. The timing varies depending on the:
- type of grassland
- location
- weather
In the lowlands, you can usually cut from July. In the uplands, you can usually cut from mid-July.
If possible, cut several times through summer and autumn to collect a range of early and later seeding species.
How to harvest seeds
There are different methods for harvesting seed. You can:
- brush harvest
- vacuum harvest
- collect by hand
You may need an Animal and Plant Health Agency (APHA) licence if you brush harvest or vacuum harvest.
The best method will depend on:
- how many seeds you need
- the size of the donor site
- whether you can use machinery on the donor site
It’s best to harvest seed:
- when the seeds are mature
- on a dry day after any dew has been burnt off by the sun
Brush harvest
You can use a brush harvester to collect a lot of seed in a short timescale. Try the brush at different heights to find the setting that collects the most seed.
Harvest throughout the season to collect seed from early, mid and late flowering plants. Brush only once each time to help reduce the amount of vegetation you flatten with machinery.
Vacuum harvest
You can use a handheld vacuum harvester over smaller areas. Harvest throughout the season to collect seed from early, mid and late flowering plants. Vacuum harvesters do not capture all the seed and can miss some target species.
If you have uneven ground, a vacuum harvester may be better than a brush harvester. A brush harvester might not collect all the seed from depressions in the ground.
Collect by hand
You can collect by hand when you cannot use machinery, like on steep slopes. This is slower but lets you select the species you want.
Dry the seed
For best results:
- dry collected seeds straight away
- sieve seeds to remove larger stalks and leaves – you can create a large sieve out of a wooden frame and chicken wire
- spread seeds thinly on newspaper, so they dry quicker and do not warm up and become infertile
- regularly turn the seed
Store the seed
A suitable place to store seed is:
- cool, between 2°C and 5°C
- dark
- dry
- rodent-free
Store dry seed:
- in small containers, to help prevent heat build up
- temporarily in paper bags or envelopes
- in airtight containers if you wish to sow next spring
