How to Apply Lawn Fertilizer
There is only one way to spread fertiliser on the lawn and that is with a spreader. Preferably a broadcast or rotary spreader.
Broadcast or Rotary Spreaders
These use a very simply spreading mechanism and will fling the fertiliser out on to the lawn as you walk or crank the handle. As long as you walk in straight lines and at a constant pace the spread will be very even which is exactly what you want. As long as you use a fertiliser without pesticide such as a Lawnsmith Fertiliser, it doesn’t matter if some goes into the borders as it will feed border plants rather than killing them as would happen when using weed and feed type products.
Drop Spreaders
These are primarily used for weed and feed or 4in1 products as they drop the product vertically downwards preventing product from going anywhere else. The downside is that unless you are millimetre perfect with where you walk, and have lightening fast reactions to start and stop the fertiliser flow you will get uneven spreading which will create colour variations or burn marks. Wherever possible use a good fertiliser without pesticide in a rotary spreader.
Rotary Spreaders; you get what you pay for!
In theory all rotary spreaders should do a good job but cheap ones don’t have the fine adjustment of middle priced machines. The cheaper spreaders are usually operated by cables which stretch meaning last seasons settings are no longer accurate which is a pain!
The downside therefore is fertiliser not going on at the correct rate which may waste fertiliser and money or potentially burn the lawn if the rate ends up too high.
Please see our Spreader Buying Guide for more help on the best spreader for you.
Putting the Correct Amount of Feed on the Lawn
So, you’ve got your fertiliser, put together your spanking new spreader, you’ve checked the setting number on the spreader setting chart and off you go, or do you?
Spreader setting numbers are a guide only. The known factors are the spreader and the fertiliser which will have been calibrated together. The unknown is how fast you walk which influences the spread width and therefor the amount per square metre being applied. A person walking at 2mph will put at least twice the amount on compared to somebody walking at 4mph. Therefore, spreader settings are a very rough guide only.
You can over come this problem in several ways:
- Weigh out the correct amount of fertiliser for your lawn before starting
- Spread by the double pass or overlap method. In other words, use a setting for double pass and do the lawn once. This should mean you have enough left over to repeat the application. If you have:
- More than half left apply this on the same setting from a different direction where possible; perhaps cross-ways. If you still have some left after this second run then decide whether to do another run or hold off. You should now consider a slight increase in the spreader setting for your next application of this fertiliser.
- less than half left then be grateful at least all the lawn has been fed without over dosing. Adjust your settings downwards next time you use that feed so that you can do two half rate applications. Watch the Double Pass Animation
- Watch the video 'Calibrate your spreader'
If you want to practice with your spreader in a totally safe manner use rice. It is white so you can see where it goes, it will not harm the grass if too much goes on, and as it is a carbohydrate it will feed the lawn a little. Not the cheapest or best feed but useful as an aid to becoming confident with your spreader.