When is the first time to mow the lawn after sowing / reseeding?

Neither a look at the calendar nor the number of days allow a well-founded conclusion about the first lawn cut after a new sowing. If you sowed in spring, the growth may progress more quickly due to warm weather than in the cooler autumn. In contrast, the height of the blades of grass serves as a reliable guide for the appropriate date. Ideally, a distinction is also made according to the type of lawn sown:

• Sports and play turf: 70 to 75 mm
• Ornamental lawn: 80 to 85 mm
• Shadow lawn: 100 mm

It is worth taking out the folding rule to determine the exact height. A misjudgment by eye can seriously affect your new lawn. If the lawnmower is used prematurely, the individual noble grasses have not yet sufficiently taken root in the ground. The fatal consequence is that numerous seedlings are torn from the earth together with their roots. Likewise, you’re doing your lawn a disservice if you let it flourish uncut for too long. If the stalks clearly exceed the maximum height of 100 mm, their vegetation point shifts upwards. If the lawn grass is now cut to the ideal height of 45 to 50 mm, the delicate stalks get a vegetation shock in the floral limbs. In this case, you are still a long way away from an even density of grains.

Perfect framework

The height alone is not decisive for choosing the ideal date. Only in combination with suitable weather conditions and the current condition of the green area will you achieve the best result with the first cut of the lawn. You should therefore include the following aspects in your decision:

• The weather is dry and overcast without blazing sun
• The nighttime temperatures do not drop below 5 degrees
• The lawn is dry, but not dried out

If the sowing took place in autumn, you have the practical option of calculating the perfect date from the point of view of temperature. To do this, add up all daily maximum temperatures from January. As soon as the total exceeds 180, you can mow the lawn for the first time, provided it has reached the recommended height.

Flawless cut with sharp knives

All efforts to choose the right time for the premiere of lawn cutting come to nothing when a lawnmower drives the area with blunt blades. Instead of an even, velvety green grass surface, fuzzy sickle blades leave frayed stalks behind, which gives your lawn a disheveled appearance. Last but not least, the battered grasses are a welcome target for pathogens and pests. Experienced hobby gardeners therefore use the quiet winter time to maintain the lawnmower and meticulously sharpen the cutting unit.
Furthermore, the level of the engine speed makes an important contribution to an even lawn cut. The cutter bar on a motorized lawnmower should rotate at a minimum of 3,000 revolutions per minute. This speed ensures that the stalks are cut off smoothly without causing unnecessary cuts.

Mow properly according to the one-thirds rule

If all the premises have been met for the first cut after laying your new lawn, the result depends on the professional implementation. Since every mowing means pure stress for the noble grass, the cutting depth has to be chosen carefully. If you shorten the individual stalks too much, the lawn will not have fully regenerated by the next mowing. This ultimately leads to an accumulation of stress with corresponding consequences for vitality and scar density. Therefore, do not mow more than a third of the height of the plant per pass. If the first cut after re-sowing is at a stalk height of 80 mm, set the lawnmower to a cutting height of 50 mm. If you only take action at a height of 100 mm, please mow in stages initially to 70-75 mm and then to 45-50 mm.

Do not step onto the lawn beforehand

In the creative ornamental garden, the lawn is mostly surrounded by flower beds, hedges or perennial beds. These also require maintenance, just like the green area. Please do not deal with this work immediately before mowing if you have to enter the green area to do this. If a lawn is trodden down in an uncut state, the stalks only gradually straighten up again. This means that the mower does not capture all the grasses, so that you end up worrying about an uneven cutting pattern.

Accurate cutting width

So that your new lawn looks like it has been peeled from an egg after the first cut, please pay attention to the cutting width. As a rule, the horizontal wheel spacing of a lawnmower is designed so that the mowed path is between 30 and 55 cm wide, limited to the right and left by the track of the wheels. You create a streak-free and seamless green area by aligning the lawnmower so that exactly one wheel width extends into the already cut grass strip.

Always remove clippings

The lawn mower does not always have a collecting basket. At the end of the mowing, the clippings are spread out over a large area of ​​the green area. While such a layer of mulch is advantageous in the ornamental and useful bed, it is associated with the risk of rot and disease on lawns . So please take the time to clear the lawn afterwards. An exception applies to cutting lawns with a mulching mower. These devices shred the clippings so finely that they fall between the stalks and act as organic fertilizer.

Mow across slopes

If the freshly laid lawn is on a slope, please mow across the slope from the first cut. Thanks to this measure, you can create a uniform cutting pattern on embankments. In addition, you reduce the risk of falling under the mower.
Tip: Regular mowing creates a robust density of grains and underpins the lawn’s resistance to all kinds of stress. Consistently cut high-quality ornamental lawn every 7 days. A playground and sports lawn should be mowed twice a week, whereas shady lawns are content with one mowing pass every 10-12 days.

Note rest periods

The use of a motorized lawn mower is associated with a correspondingly high level of noise. It is therefore not surprising that a passage has been integrated into the 32nd Federal Immission Control Act with guidelines for the operation of such devices. Please keep the following requirements in mind when you switch on the lawnmower for the first time after reseeding and afterwards:

• Hours of operation for petrol lawn mowers: Monday to Saturday from 9 a.m. to 1 p.m. and 3 p.m. to 5 p.m. – not on Sundays and public holidays
• Operating hours for mowers with the EU eco-label: Monday to Saturday from 7 a.m. to 8 p.m. – not on Sundays and public holidays
• Operation of hand mowers: continuously permitted without restrictions

All whisper-quiet cordless and electric mowers have been given the yellow-blue EU eco-label. Please note that these are general guidelines. States and municipalities have the right to individual regulations. It makes sense to inquire with the responsible authority before mowing the lawn for the first time.

Conclusion
The first cut of a newly laid lawn is both the end of the new sowing and the beginning of the maintenance program. Various criteria must be taken into account in order to make the right appointment decision. The stalks should have a length of 80 to 100 mm. Mild, overcast and frost-free weather is an advantage. It is also important to note that a mower is used with freshly sharpened blades that rotate at least 3,000 revolutions per minute. If you still follow the one-thirds rule, do not step onto the unmowed grass area in advance, sweep away the clippings if necessary and observe the statutory rest periods – you’ve done everything right.