BY the time you read this in April, many larger seeds could already be in the ground. But it is not too late!

What all seeds require to germinate is a moist environment at the right temperature. Most prefer to be in the dark too.

Once germinated, seeds require a medium into which roots can grow to find air, water and nutrients and through which the shoot can penetrate to find sunlight, for the energy it provides.

Most UK soils provide these conditions sometime in March and April, when the soil warms up in the spring sunshine and is dried out by March winds.

Global warming is however affecting the weather and making it difficult to predict ideal sowing dates, so you need to understand your soil and how to handle it, more now than ever before.

Your soil is possibly your greatest asset and to learn how it works and how to treat it, is a fascinating exercise and one which you are unlikely to complete in one lifetime!

If soil is too cold or too wet, seeds will not germinate. They just lie there until they rot, or some pest eats them. Too dry and they don't germinate either, or having germinated, the young plant dies of thirst.

These rules don't apply to weed seeds of course. They will lie in the soil for years, until the opportunity to grow arises! Sods law isn't it?

There are so many similar situations in farming, probably because we are trying to grow plants, which are not indigenous to our conditions, whilst the weeds are.

Creating the right conditions

"Friable" is the word we use to describe the soil when it is in the right condition for sowing.

Describing this is going to be difficult to say the least!

Soil moisture

The soil should be crumbly, something that air and moisture can move through easily. More like slightly moist, broken biscuits, than flour.

If it sticks to your boots, tools or spade, it is too wet.

If a handful of cultivated soil sticks together in a tight ball after squeezing it, it is too wet.

If a handful falls apart after squeezing, it is too dry, so you want something in between.

Soil temperature

Judging the right soil temperature is best achieved by observing the grass and weeds nearby. When they start to grow, the soil temperature is approaching that suitable for many of our domestic plants.

Dark coloured soils in, south-facing situations, sheltered from the wind, will warm up much earlier than light exposed soils. Growth will start days or even weeks earlier and the plants in such soil will thrive, growing quickly, to a large size.

Plants seem to appreciate the opportunity to germinate and grow without any checks, and sowing too early, is to risk a period of inclement weather, which will stop growth and stunt the plant for weeks.

Sow too late and without irrigation, you risk the soil drying out, before the plant has its roots deep enough to reach the remaining moisture. It's that law again!!

It is of course worthwhile, to sow a few vegetable seeds very early and risk losing them. The result if they survive will be exciting and very rewarding. Something to boast about in the Rose & Crown!

This is not the case when sowing several acres of grass seed, costing hundreds of pounds. The financial risk is significant, so getting the timing right is important.

Sow beans first

Large seeds like beans have in their very size, a huge reservoir of food for the young seedling. They can support a shoot whilst it grows through 10cm of soil, before it sees the sun.

These large seeds do not require a very fine seedbed, so it is easier to prepare for them, in soil which is still quite wet.

A tiny cress or carrot seed must, by contrast, be very close to the surface and amongst very fine soil particles.

As a general rule large seeds can be sown earlier than small ones, but take care with those plants that are susceptible to frost when they emerge. These include Kidney beans and potatoes.

Grass seeding procedure

The spring sowing window for grass seed is very small and Mother Nature can often move it a week or two either way. Sometime in late April may now be about right.

The autumn window used to be mid August to mid September, here in the midlands, but it may be getting later now.

As usual with agriculture, so much depends on what the weather does after sowing; so first find your soothsayer.

Fertiliser

If you can find any, spread Farmyard Manure (FYM) or compost, immediately before ploughing. As much as possible, up to 125 tonnes per Ha (50 tonnes per acre).

Get this done whilst the ground is firm and dry, or the benefits will be cancelled out by the damage to the soil. Avoid spreading onto wet soil, when the machinery sinks in 5cm or more.

There are rules restricting muck spreading in winter months, particularly on waterlogged or frozen soils. Check with DEFRA.

Ploughing

Ploughing the land will, if well done, completely bury all the FYM, the previous crop, grass and weeds. No green should be showing through the ploughed land.

Autumn ploughing will allow the frost to break down clay soils (Man's land) into a friable condition, requiring only a light cultivation in the spring.

The spring ploughing of clay soils can be disastrous, particularly for the inexperienced!

The easily worked, light sandy soils, known as "Boy's or Lad's land" can be ploughed in the spring and cultivated almost immediately.

Cultivators

Following the ploughing, some form of cultivation is required to break down the large lumps of soil to achieve a "Tilth", into which the seeds can be sown. A tractor powered cultivator, known as a "Power harrow" is the ideal machine, particularly when in the hands of an experienced operator.

One or two passes may be required, depending on the condition and clay content, of the soil.

Seedbed or tilth

A good seedbed will consist of a tilth of soil, which contains mainly particles of similar size to the seeds, at the depth at which they are to be sown.

Grass seeds are tiny, similar to thin string, cut into 2 to 4 mm lengths. Clover seeds are like minute pinheads.

A seedbed to suit both of them, needs to be very fine in the top 2 or 3cm, quite fine (marble size) for the next 5cm, then golf ball size below that.

This tilth will be moist, but not wet enough to congeal when squeezed in the hand.

If too wet, leave it to dry out naturally. This process which may take an hour, or possibly several days, depending on the weather.

Allowing the tilth to lose all the moisture, will delay the germination of the seed until the next heavy rain and whilst it is waiting, every slug, insect and bird pest in the county will race in to eat it.

They don't however seem to eat the weed seeds! It's Sod's law again!

Grass / clover seed mixtures can be spread evenly on the surface, then harrowed in, or preferably drilled to a depth of 1 to 2 cm, using a conventional farmer's grain drill.

Rolling

Rolling, immediately after sowing, is vital for several reasons and the urgency of this operation, is often missed by farmers and contractors. The roller compacts the top 4 to 6 cm of soil, which has the following beneficial effects:

Soil moisture is contained. Without rolling the seedbed will quickly dry out..

Subsequent showers penetrate only as far as the seeds and don't run past them into the soil below.

The seeds are pressed into close contact with the soil particles, allowing the easy transfer of moisture and nutrients to the seed and young roots.

Pests which live in the soil, such as slugs, wire worms, beetles and the like, have greater difficulty in moving through the rolled soil to find the seeds.

Birds find it more difficult to find and eat the seeds.

Rolling levels the surface, for years to come.

Rolling twice or more, in different directions, is very much more effective.

The usual, economic seed rate is 40kg / Ha (15kg / acre) costing £75 / Ha (£30 / acre). More seed than this is never wasted, just expensive.

Adding tiny quantities of herbs, such as Chicory, Trefoil, Sainfoin and Vetch, to the mixture, adds to the expense, but is well worth while, for the benefit of the grazing animals.

Wild flower seeds may be added, but a special mixture is advisable and no FYM or fertiliser, should be used to increase fertility.

After sowing

The new ley will appear two to four weeks after sowing, firstly as a green haze over the field.

The new grass seedlings will be accompanied by every weed imaginable on emergence, but do not worry, grazing sheep or later on, a topper will sort them out.

Clover will germinate at a later date and may not be evident until the summer of the second year. Clover prefers Lad's land.

There will be little or no production from a newly sown ley for two or three months (Half the summer), so you must allow for this when calculating stocking rates.

Do not introduce grazing animals, particularly horses or even cattle, until the grass is well established and 10 cm tall and then only if the soil is dry. They will destroy it with their feet.

Autumn sown leys are less affected by this phenomenon, because they are establishing whilst livestock are being wintered indoors anyway.

The cost of new grass:

Cultivation Costs £150 - £250 / Ha, £ 60 - £100 / acre
Seed £ 70 - £100 / Ha,£ 30 - £ 40 / acre

Total, assuming no fertilisers or sprays are used £220 - £350 / Ha, £ 90 - £140 / acre

Ian Wilkinson of Cotswold seeds, is an expert on seeds for non-conventional situations. Tel. 0800 252211