Growing and Caring for your Yellow Rattle, Rhinanthus Minor

This article aims to help you successfully grow Yellow Rattle.


This is a pretty yellow flower found in traditional hay meadows throughout Northern Europe. It can be difficult to grow but when the conditions are right it will spread rapidly. Its spread, outside the meadow is mainly by mechanical means by being caught on machinery or in a crop such as Hay that has been harvested in July so some of the seeds are still encapsulated in the plant. Naturally it does not spread far from its parent plant. In the process of hay making the turning of the hay helps to spread this further. It does not like rough ground when germinating therefore is confined to the meadows by the hedges and verges where the grasses are not cut or grazed. The plant is a sought-after species for conservationists who try to encourage colonisation and promote bio diversity to meadows. Its preferred habitat is dry fields or meadows. It does not tolerate heavy shade as this delays germination. Its flowering period is between May and July, being at its height in late June.Hay rattle in a meadow

The seed germinates on the surface of the soil. In February or March. At this time of year the seed will have been resting for 6 months and would have stratified due to chilling between 10 to 5 degrees Celsius. Or 6 weeks in a fridge. With the right conditions and a few warm days the seeds germinate and depending on your latitude and local weather conditions it throws up a small two leafed shoot that look a bit like jagged edged stinging nettles. The energy in the seed is soon used up and if the grass is too long it won't be able to take any energy from the sun and will soon perish. This is that main reason why this seed is difficult to grow If established successful its roots will parasitize on to a grass, or clover, nearby in April/ May. Without Grass the yellow rattle will struggle to thrive and eventually perish. This fine balance between having grass but not too long is critical for the survival of Yellow Rattle.

By late May the plant should be beginning to flower, this is orange/red at the base as it opens turning to yellow in full bloom. The leaves are small as it is now taking part of its nutrients from the Grass and Clovers. Flowering continues for 4 weeks and by Early July the seed pods have ripened to Golden colour and can be heard rattling in the breeze. If sufficient Yellow rattle the grass would hardly grown and by the end of June be relatively short and easy to Cut. A lot of yellow rattle is not good for livestock so it is best to allow the Rattle to set seed thoroughly before cutting for hay. The plant will dry and crumble with little trace left in the Hay. Once the Yellow rattle has died off by Mid July the grass can grow on freely rain permitting.

Other common names, Cock's Comb, Hay Rattle, Shackle Bags.

Food plant of the caterpillars of the Grass Rivulet moth as well as a favourite nectar source of the bumble bee.

See Wikipedia for a good description.

Sowing Yellow Rattle seed

Get your yellow rattle as early as you can from a supplier that you can trust. Last years yellow rattle won't germinate as well and yellow rattle sold in a mixture in the spring also won't germinate in the season of sowing. It is always best to sow this in the Autumn of harvest.

It is important to realise how yellow rattle works to understand it place in the field as an annual in a field of perennials. It achieves this by germinating before anything else starts growing. It needs to be able to warm up, have access to moisture and light. If the seed is covered in soil it won't warm up early enough to compete with the grasses. If the grasses are too long at time of germination it won't be able to get beyond its seedling stage. and finally if there are too many seeds only the ones that have found a host plant will thrive.

The seed relies on the sun to warm the seed and not the ground for it to germinate. Its design as a flat seed will keep it naturally on the surface and its large seed coat act as a solar collector.


Yellow rattle and mixtures with it in must be sown before December of the year of harvest. Broadcast the seed into recently mowed(or sowed) grass. Divide the plot and packet into equal areas and quantities. To ensure even distribution sow each sub plot separately, avoiding windy days when the seed can be blown off course. Do not cover the seeds. Scarify and roll, graze the regrowth with sheep of cattle.The animals or machinery will remove the grass and help to tread the seeds into the ground. Ideally grass should be short in January, and every January so it may need mowing again then. If only a small area is to be sown on a large field choose a line across the field as the seed will tend to spread in following years.


Germination begins between February and March in the southern England and later in shady areas or further North.  It is so good at germinating that it is partly its downfall. Most of the seeds will germinate but only a few will survive for one of the following reasons: 1)because they cannot find a host grass 2)the grass is too long 3)dry weather.  It is advisable to keep stock off these fields from February till August. Allow the yellow rattle flowers to ripen and the seeds to blow out. Some of the seeds will be held in a pod so it is advisable to thrash these out before cutting especially if you are using a mower with a collector.


In any event leave cutting as long as possible. September or October is ideal. Yellow rattle stops grass growing between May and July. Leaving the cutting later can be more difficult but the results will be rewarding.

Beware. This is an Annual and it will die out in a year if

  1. the plants are not allowed to set seed,
  2. the grass is too long at the beginning of the year.


We have lots of yellow rattle in our fields and make and sell lots of hay for horses with no problem. It is all made after the yellow rattle has gone to seed and the plants are brittle and mainly crumble and fall out of the hay. some still remains especially the stalks. So there seems to be no problem with feeing it dry. We have not seen any evidence that it is poisonous to live stock when green and our sheep graze in the fields from March to April when it is at its most palatable. When it is mature it does not have many leaves so again is not very palatable. As with all things if there is nothing else for the live stock too eat, too much Yellow rattle, of anything, could be a bad thing. However it has always been in traditional hay meadows and is often made in to hay in June without any problems.



In Spring go round your wild flower meadows and hoe out any spear thistles with a mattock at the rosette stage.

In late June dig up any Docks and ragwort. put straight into a large bag or wheel barrow to contain any seed that may fall off. Use a fork to dislodge loosen the root, or turn the sod over and extract the entire root.

Creeping thistles need to be pulled in Late June. They are easy to pull as long as you don't try to pull any grass at the same time. Need good pair of gloves for this one. Put straight into a bag. May need to repeat again as they share a common root system. If persistent and thick cut in early June also or use a selective herbicide such as Grazeon.

Keep an eye on Himalayan Balsam as this is starting to become invasive in many places. I suggest keeping this in control before it get out.

Burn all of these species and do not put then on the compost heap.

Bracken, Roll or cut this when it is young. If it is a big problem use a herbicide for bracken such as asulux.

When using herbicides please make sure you have the appropriate training or use a contractor.


Some people have asked how to manage yellow rattle in there meadows it it gets too dominant. To reduce yellow rattle is relatively easy: Roll or chain harrow the field in April or May will severely reduce it. The later you leave it the more effective rolling is, however you run the risk of damaging other seedlings in the meadows such as orchids.Graze in May and June, Cut in mid June or allow the grass to grow over winter so the seeds can't germinate.I would prefer the roll in late April and don't stock the fields after a crop has been cut.that should do the trick and allow maximum grassland perennials to still thrive in the meadows.


Keep an eye on sow thistles, spear thistles, ragwort and Docks, dig up as soon as they appear in the spring.


Avoid areas shaded by large trees as the seed will struggle to germinate. Where trees cannot be avoided ensure that the leaves are removed as soon as possible. this will have the effect of reducing the fertilisation of the ground by leaf mulch and uncovering the seeds in spring. Dry banks can also be a challenge as they often dry out taking the yellow rattle and finer grasses out as well. Try introducing some plantain into the bank as a drought tolerant ground cover as well as some meadow grasses. Wet and boggy ground will support yellow rattle as long as it can be cut short in the summer and after grazed in the autumn. If it is too wet to manage in the winter then consider choosing some patches which can be easily managed within the area.

Goren Farm has signed up to the Flora Locale terms of code of practise to only sell local provenance seed that is of the highest quality. Our seed has been deposited in the Kew Melliumn Seed Bank as local provanance and Native Origin Yellow Rattle seed.

Goren Farm Online store,


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