If you are planning on planting a hedge (or creating a flower bed or vegetable border etc.) onto bare soil that has a poor structure and/or is in need of extra fertility then it is worth considering a green manure…
The technique is simple and requires more patience than effort. Fast growing plants are sown onto the bare soil and, once they have flowered, are cut down and dug into the soil.
• While growing, the Green Manure’s foliage stifles undesirable weeds while their roots hold the soil together. The plants also protect the soil from rain compaction and attract useful wildlife.
• When they are subsequently dug into the ground, valuable nutrients that otherwise would have been diminished or lost, are returned. If you have included plants from the pea and bean family, their famous nodules will fix nitrogen into your soil.
• Other benefits of green manures include protection of the soil surface from compaction by rain and shelter for beneficial insects such as ground beetles.
When to Sow
• Late summer to early autumn
Where to Sow
• Green Manures generally work best in sun, though some shade may be tolerated
How to Sow
• You can sow the seed in rows if you wish, but a simpler and far less time-consuming broadcast method works just as well – don’t forget to rake over once the seeds are sown
• Green Manures are, by their very nature, maintenance free – though watering may be required during prolonged hot and/or dry weather
When to Dig In
• The Green Manure can be cut down the following spring and left to wilt for two weeks. It can then be dug in to a depth of c.25cm
• Once dug in, leave the area alone for 2-3 weeks (or longer) before planting your hedge, rose bed or vegetables
• If you prefer, the green manure can be left untouched for a couple of years while you finalise your plans!
What to Sow
The seeds are readily available including specially selected proprietary mixes of seeds for particular situations. Here is a few of the most popular varieties many of them include:
Bitter blue lupin
Essex red clover
Winter field bean