How To Cut Wet Grass And The Best Petrol Lawnmowers To Do It With.

How To Cut Wet Grass And The Best Petrol Lawnmowers To Do It With

Anyone can simply say don’t cut the grass when it’s wet. What happens if you have no alternative?

Perhaps you are offering a lawn care service or only have access to certain properties on particular dates?

Sometimes, unfortunately, cutting wet grass is unavoidable.

In this article, I’m going to talk about which lawnmowers are the best choice when it comes to cutting and boxing up wet grass.

I’m also going to include some helpful tips on cutting wet grass that can massively improve the process and which petrol lawnmowers are the best for tackling this job and why.

What’s Wrong With Cutting Wet Grass?

If you are new to cutting grass or considering starting up a lawn care business with no previous experience you may wonder what is the problem with cutting grass when it’s wet?

There are a few main problems.

One problem is that when the grass is wet it simply doesn’t cut as well as when its dry. The grass will clump together and stick to the underside of the cutting deck and if not regularly removed the deck will rot in no time at all.

Another problem is when the grass is cut whilst wet collecting the trimmings in a grass box becomes almost impossible without the right equipment.

There needs to be enough power and lift to blow cut grass back into the grass box and when the grass is wet it tends to stick together in clumps and clog easily whilst attempting to reach the grass box.

There are many ways we can remedy most of these problems. Not just by waiting until the grass is dry but by knowing what design features and servicing we can do and how to choose a petrol lawnmower that will help ease the process. There are many simple options.

You can find lots more information and start repairing lawnmowers for profit by checking out my online training here

Let’s Start With Standing Water 

First things first let’s start simple. Never use an electric lawnmower in wet conditions! (I have seen this done!)  Cylinder lawnmowers will not cut in wet conditions either.

You will need a rotary petrol-powered lawnmower.

Standing water needs to be removed before any cutting can begin. Wet or damp grass is one problem but standing water is another. One simple way to remove standing water is to siphon it.

Fill a hose pipe with water and close it off at both ends with a shut off valve. It’s important that the hosepipe is completely full of water and no air is remaining.

Place one end of the hosepipe in the standing water and open the shut-off valve, run the other end of the hosepipe to the lowest ground level possible and release the valve.

This will siphon any standing water.

The lower you can get the drainage end of the hose the faster it will siphon.

Damp Or Wet Grass

With any standing water removed you may want to squeegee the lawn before mowing. You may not think this would help much but believe me it does!

Take a hosepipe, preferably full of water and simply drag it back and forth across the grass. This process knocks any water from the grass down into the soil and makes cutting efficiency much better.

If you have a leaf blower it may also be worth taking the extra time to blow some of the extra water from the grass.

If your grass is overgrown you will always have problems when cutting. I suggest strimming the grass to a reasonable length if this is the case.


What Helps Cut Wet Grass?

As discussed removing any excess water before mowing is advisable. So what next? The grass is still wet and it still needs cutting. There are many tips and tricks for cutting wet grass with a petrol lawnmower. Let’s start with height adjusters.

Height Adjusters.

Never purchase a petrol lawnmower without a height adjustment option. They become completely useless once the grass reaches a certain height, the ground is soft or the grass is wet.

If your lawnmower has a height-adjustable setting set it to the highest setting possible before attempting to cut wet grass.

Setting the height like this can save the drive belt (if fitted) becoming overrun with cut wet grass. The last thing you want is the drive belt coming off and being cut into pieces. Make sure you have a belt guard fitted also.

You will need to trim the wet grass in stages starting at the highest possible height and lowering gradually. This gives the blade less work to do and will help transfer wet cuttings into the grass box more easily.

When purchasing a lawnmower for cutting grass in all conditions make sure it is height adjustable. Some lawnmowers have a single lever for adjusting the overall height rather than individually on each wheel.

I suggest a single lever height adjuster for cutting in all weather conditions as it can be quickly and easily adjusted.

Overlap Half A Width

When cutting wet grass only overlap the first cut width by half the width of the lawnmower. This way the lawnmower is cutting less grass and has more time to help transfer wet cuttings to the grass box.

Slow and steady wins the race.

There is nothing worse than having to stop a lawnmower to clean out the chute and grass from obstructing the blade.

Cutting half-width sections by overlapping the grass that’s already cut will definitely save you some time in the long run.

Chute Size

When wet grass is cut it clumps together and it makes transferring it to the grass box more difficult.

Cutting wet grass and trying to collect it in a grass box/bag is never fun. If it’s your only option there are some things we can do to help the transfer of grass from cut to box/bag

The angle of the blade provides backlift to the grass to transfer it to the grass bag/box.

For the cut grass to first make it to the grass box it needs to pass through the chute.

Chute size is incredibly important when cutting wet grass. The smaller it is the more easily grass will clump together and not transfer to the grass box. It will eventually stop the lawnmower cutting altogether as the blades simply can’t cope.

Trying to cut wet grass and hoping it transfers to the grass box when a lawnmower has a small chute is comparable to Augustus Gloop being sucked up the chocolate pipe in Willy Wonka And The Chocolate Factory. It simply doesn’t all fit. (easily)

To see what size chute a lawnmower has, lift up the grass box deflector and remove the grass box. Most small lawnmowers only have a chute about the size of your hand.

To cut wet grass and box it up choose a lawnmower with a larger chute size. It will help enormously.

Sharpen The Blade

This is possibly the best thing you can do to help cut wet grass. Having a sharp blade is essential.

The angle of the blade is important too as it provides the backlift for transferring the cut wet grass to the grass box.

Many gardeners will look out for specific lawnmowers just to purchase then use in wet conditions.

Keeping the blade sharp and selecting a lawnmower with a large chute will make a huge difference when cutting wet grass.

It makes sense to have the blade professionally sharpened as this will maintain the correct angle of the blade. They will also balance the blade for you which will keep vibration to a minimum.

Empty The Grass Box

Emptying the grass box more frequently can help when cutting wet grass.

Wet grass becomes heavy very quickly so by emptying the grass box more frequently you can reduce the weight of the lawnmower and make it easier to push and more efficient when cutting.

Some lawnmowers feature a roto-stop blade brake.

This is a very handy feature as it enables you to empty the grass box whilst the engine remains running and the blades stop turning.

To find out more about roto-stop clutch systems take a look at this lawnmower and read the product description.

Honda HRX476HY 19-inch Wheeled Hydrostatic Petrol Lawnmower

Integrated Blower Fans

Some high-quality walk behind petrol lawnmowers feature a powerful integrated blower fan that helps transfer cut grass to the grass box.

John Deere R43S Petrol Lawnmower

This John Deere R43S Petrol Lawnmower is a solid example of a lawnmower with an integrated fan blower and would be an excellent choice for anyone needing to mow in all conditions. It also features an aluminum cutting deck with a 15-year warranty as standard. It also has a single point height adjuster which would be useful as you can very simply and quickly adjust the height.

Power is important when cutting wet grass and John Deere has fitted a very powerful Briggs And Stratton 5.5 HP engine.

Peace of mind for anyone working in all weathers.

Get A Powerful Engine

Power is critically important for efficiently cutting wet grass. When power works in conjunction with sharp blades at the correct angle it creates excellent backlift that is strong enough for collecting wet grass.

I would suggest 4.5 HP as a minimum to cope with wet conditions. Honda, Briggs And Stratton and Toro provide excellent options and are fitted as standard on many quality petrol lawnmowers.

Take a look at this playlist on how to repair and service your own lawnmower

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Side Discharge

Side discharge is possible on some lawnmowers. There are advantages and disadvantages to side discharge in wet conditions.

One advantage of side discharge is that it eliminates the problem of having a small chute. The wet grass clippings are discharged out to the side of the lawnmower.

The disadvantage is if you are cutting near buildings or patio areas, for example, the side discharge tends to throw the grass cuttings everywhere.

Side discharging is advantageous when cutting larger areas away from well-kept flower beds and patio areas. The grass will still clump together when side discharging so raking the grass after cutting is advisable.

Self Drive Petrol Lawnmowers

If you are looking to set up your own lawn care business and work in all weather conditions a self-drive lawnmower is advisable. Wet grass is heavy when collected in the grass box and pushing can become much more difficult.

Having a lawnmower with a self-drive and a blade brake clutch would be an excellent choice as it saves having to restart the lawnmower each time you empty the grass box.

My choice for a lawnmower with these features would be Honda HRX537HY 21-inch Wheeled Hydrostatic Petrol Lawnmower with a large 21-inch cut and large chute size this lawnmower boasts a 187cc engine (5.3 HP) engine and a roto-stop blade brake as well as a large 88-litre grass bag.

It also has a hydrostatic self-drive designed to keep power under full load when cutting.

Attempting to cut wet long grass without the help of a reliable self-drive isn’t recommended.

Heres a video form my Youtube channel on Self-Drive Problems

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Which Petrol Lawnmower Is The Best For Cutting Wet Grass?

If you take a look at any online forum for lawn care professionals there is always a debate as to which is the best all-around equipment. These forum posts usually provide valuable information but usually end up in online arguments. People can get really passionate about these subjects.

After research, I have discovered that Rover lawnmowers and Toro are a popular choice.

The Toro 20952 recycler is mentioned many times as a good solid choice for commercial and home use. It features many of the features I have recommended including electric key start self-drive and adjustable cutting heights.

This lawnmower is also capable of mulching and side discharging of grass as well as the option to collect grass in a 60.5-litre grass bag. With all these features it makes a great all-around choice

This would be an excellent choice of lawnmower giving you so many options and the reliability of the highly respected Toro brand.

This would be my choice if I were to buy a lawnmower for use in any conditions. Although it doesn’t have a roto stop blade brake it does offer may different trimming options and it features adjustable and foldable steel handles.

Toro is an excellent choice and is often highly rated by professionals both online and off.

How To Stop A Lawnmower Cutting Deck Becoming Rotten

This is the biggest reason people have to replace a lawnmower. The problem with cutting any wet grass is that it clumps together and will inevitably stick and dry to the underside of the cutting deck.

Some lawnmowers come equipped with a deck wash facility. This is an excellent feature for looking after a lawnmower cutting deck.

This feature works by attaching a hosepipe to the upper side of the cutting deck and turning on the water. The deck is then conveniently washed off underneath so any remaining grass is removed after cutting.

This McCulloch M46-125 Petrol Wheeled Rotary has an underside deck wash facility. There are various lawnmowers that offer this feature.

To stop any lawnmower deck becoming rotten only takes a small amount of time at the end of each cutting season.

Remove the spark plug and lean the lawnmower sidewards with the exhaust pointing towards the ground. Try and make sure the gas tank is reasonably empty.

Take a scraper and wire brush and remove any excess grass that is stuck to the underside of the deck. If the lawnmower has a belt guard then remove this also so you can access the whole underside of the deck.

I usually paint the underside of the lawnmower cutting deck once a year with Hammerite metal paint. This helps to prevent rust and rot.

Doing this small procedure once a year will save you purchasing a new lawnmower long before you should need to.

Cutting Discs

Some lawnmowers have a cutting disc that sits beneath the cutting deck and the blade. This disc will help protect the underside of the cutting deck.

Hayter lawnmowers often use this setup and I’m often impressed with the cosmetic condition of Hayter lawnmowers when I purchase them to repair for profit.

Hayter has held the royal warrant for supplying lawnmowers for the Queen of England since 1960 so you would expect the quality to be excellent. I can tell you from my experience it usually is.

Final Thoughts

I have tried to offer useful advice and equipment to cope with the challenging conditions of cutting wet grass rather than the usual “Don’t cut wet grass” article.

It does, however, go without saying that having to cut wet grass should be avoided if at all possible.

Chute size, power, and sharp blades are incredibly important when attempting to cut wet grass and any other features such as roto-stop blade brakes and hydrostatic drives are helpful features.

Never attempt to overlap cuts by more than half a stripe and be sure to do everything possible to dry the grass before cutting.

One piece of advice I would highly recommend would be to ask a lawn care professional about which equipment they use in adverse conditions. They are often more than happy to share their experiences with you.

My own personal choice would be Toro 20952 recycler as I believe this is a great all-around choice especially with the number of trimming options. It’s very versatile and all the Toro equipment I have worked on has been excellent quality and spares are easily sourced.

I really hope this article has offered some useful information on how to cut wet grass and the equipment on offer to help you do it.

Be sure to see the recommended products page for more information and advice

You can find lots more information and start repairing lawnmowers for profit by checking out my online training here

Happy Mowing

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