Preparing a seedbed for Grass Seed

[Grassman]

Applying the seed is around 10% of the entire process required to maximise germination and establishment of a lawn, landscape or pasture area from scratch.

A seedbed (of any size) must be free of weeds, rocks and any other debris but most of all it must be firm, especially after cultivation. If the soil is still all 'fluffed up' when the seeds germinate the developing fine, hair like roots will be prone to very quickly drying out and withering away.

The soil must be consolidated. Roll the area until you can walk over it without sinking into the surface.
This is particularly important for sites which are to be level and/or smooth as low, soft spots over the seedbed are likely to subside further over time so can be levelled or filled during this process.

Once the area has been firmed down the following objective is to produce a 'Tilth'.
This is a layer of very shallow, loose and fine soil over the entire seedbed no more than 5-10 mm deep.
A tilth can be created by shallow raking or lightly harrowing the surface of the prepared seedbed.

Sow your grass seeds at the recommended rate by hand or with an appropriate seed spreader.
Two passes at half rate can give better overall seed distribution.

Lightly rake or harrow the surface to mix the seeds into the tilth. This causes the seeds to be distributed at various depths leaving some seeds on the surface and some covered by soil up to 10mm deep. This approach minimises the effects on germination of any following adverse weather conditions post sowing. The deeper seeds may well rot or 'damp off' should the weather turn particularly wet but the seeds on the surface have a good chance of germinating. Should the weather turn hot and dry or worse dry and windy then the seeds on the surface will not germinate as quickly as those protected by soil.

Finally and MOST importantly; lightly roll the entire area to put the sown seeds into firm contact with the soil.

IN FACT, IF YOU PERFORM NO OTHER PREPARATION WORK THEN AT LEAST ROLL THE SEEDS INTO THE SOIL AFTER SOWING

This maximises the absorption of soil moisture by the seeds and allows the developing roots of emerging seedlings to work immediately and efficiently resulting in faster, more uniform and stronger establishment of the seeded area.

Cultivate - Roll - Rake - Seed - Light Rake - Light Roll.

[Grassasman]

Hi,

I am looking for some advice on the following please:

I built a new house last year and had top soil put on top of the existing building site (400 square meters).  I killed any weeds with ‘Roundup 3000’ last October but missed the window to lay a lawn due to frost.
I have killed any surface weeds and dug up any large annuals that have come through in the last week.
I have hired a cultivator, roller and spreader for the weekend and bought 25kg of hardwearing lawn seed plus fertiliser.
I plan to cultivate the ground, role it this weekend and put down the fertiliser, how long should I wait until I distribute the lawn seed?

Regards,

[JAMES]

I would usually recommend a delay of 5-7 days (post rainfall) before sowing if at all possible but this very much depends on the brand of fertiliser used.
Some contractors apply pre-seed fertiliser and grass seeds together and get perfectly good results.
A neighbour of mine did just this 3 weeks ago and his lawn has germinated very well indeed.
The main risk comes from damage being caused to the fine, hair like roots of smaller grass species post germination, especially when using quick release fertilisers.