Question
I am in PA and have a new lawn. It was recommended that I put 10-20-20 fertilizer down. I have picked up Arrow 10-20-20 but nothing on the bag indicates what setting to put my Scotts Broadcast to. Any feedback will be appreciated.
Thank you
Vern

Answer
Check the back of a Scott's Turfbuilder for recommendations. You need to open up considerably more than the recommended due to fact that the 10-20-20 is only half to a thrid as strong as most Scotts fertilizer (with respect to nitrogen which is being used to dose the lawn).

You can do a double check. You will need to apply approximately 10 lbs of fertilizer per 1000 sq feet if you are using 10-20-20.

This means that if you have a 15,000 sq feet lawn area, you will need 10 x 15 = 150 lbs of fertilizer mix. If you have a 18,000 sq feet lawn you would need to add 10 x 18 = 180 lbs.

Use a medium or medium/high setting and run over the lawn once. Check how much product was used (1/2 bag, 1/4 bag, etc ?) and then calculate how many times you would need to run over the lawn again.

Example: Say you purchased a 75 lbs bag and apply to 5000 sq feet of lawn area. You would need 10 x 5 = 50 lbs so you would need 2/3 of the bag applied to your lawn.

The 50 lbs were calculated as 5,000 sq feet divided by 1,000 (= 5) multiplied by 10 (as in 10-20-20 .. the first number which is nitrogen). E.g. 5 x 10 = 50 lbs.

First fill the spreader with 2/3 bag (50 lbs) if it can hold. Then run over the lawn one time. After this time check how much product was used. If 25 lbs were used, you would need to run over the lawn again one more time; or in future use a wider setting.

In general, use a wider (more open) setting than recommended on most Scott's fertilizer bags because your 10-20-20 is 1/3 strength of 29-3-4 (the most common Scott's fertilizer).