Question
Hi,
I am looking for low nitrogen slow release fertilizer to be used for cacti. Not much luck yet. The best I could find was 15-15-15.
Do you know of any slow release fertilizer that has composition more suitable for cacti? Where P and K contents would be higher than N.
Thank you.
Victor Ober.

Answer
A common fertilizer is 5-10-10 and most garden centers should stock this or could order it. It sells typically in 5 lbs bags.

You can also try to look at lawn fertilizers in larger garden centers. I have found a 10-18-20 lawn fertilizer in 40 lbs bags. The ratios are 1-2-2 (similar to 5-10-10 which also has ratio 1-2-2). The two types vary only in the amount you add (you would need to give more 5-10-10 than 10-18-20).

Finally, you can try to look for some Tomato fertilizers. These are typically 5-7-8 or similar, e.g. with lower nitrogen and higher phosphorous and potassium.