Understanding the Numbers on your Fertilizers

Buying fertilizer can be confusing!  What do those numbers mean on the bag? What should I get? 

There are several ways to interpret, but I will help you understand the world of fertilizers!

First, there are 3 numbers on all bags of commercial fertilizers.

They are always in the SAME order.

N-P-K, which stands for ...

N-Nitrogen
P-Phosphorous
K-Potassium

This should take you back to chemistry class.  Well, gardening is a lot like chemistry!

This is 13-13-13

NITROGEN

The first number is Nitrogen. This promotes healthy growth of the plant.  It also helps create a green color in plants.  

If you want dark green grass, you want a high Nitrogen number.  

PHOSPHOROUS

The second number is Phosphorous. This helps promote flowering in flowering plants, bushes, and trees.  This. also, promotes healthy roots and seed development.

So, if you have new grass or new bulbs, a high phosphorous number on a fertilizer will help establish roots!  If you want your flowering plants to bloom and bloom... use a high in phosphorous fertilizer.

POTASSIUM

The third number is Potassium.  Plants use potassium for overall health.  It helps turn Carbon Dioxide into Oxygen.  This will promote root and stem growth.  

So let's recap! 

For new grass:  13-13-13

For grass that is overrun with weeds: weed killer and 13-13-13

For established lawns:  29-0-5 (just use a high Nitrogen level, low Phosphorous level, and small to medium Potassium level)

All purpose plant food (shrubs, flowers, vegetables): 12-4-8

Roses: 9-18-9

Flower BLOOM BOOSTER: 10-16-10

Tree & Shrub: 15-10-9

Tomatoes: 18-18-21

Fruits & Vegetable (general): 9-4-12

Indoor Plants: 6-12-6

Cacti & Succulents: 2-7-7

Just remember, check the numbers and know what you are going to use it for. Fertilizer is a key to beautiful grass, flowers, and a prosperous garden!

Happy Gardening!