Most anyone that grows any plant knows it needs certain nutrients in order to thrive. The challenge if often knowing what type of fertilizer to give what plant and when.

One of the most important things you can do in understanding what your plants need is to have your soil tested every year or two.  Soil testing is the only sure fire way to know what nutrients are missing  and what you should be supplementing.

The reality is most of us don’t have the soil tested and therefore just apply fertilizer anyway.  A few basic rules about fertilizer will help you know what and when to apply it.  

Nearly all fertilizers have 3 numbers on the bag or container.  These numbers represent the amount of nitrogen, phosphorous and potash, by weight in the bag.  The reason the numbers won’t add up to 100 is there are other fillers and micro-nutrients also contained in fertilizers.

Use this saying when you think about those three numbers-Up, down and all around.  The first number, the nitrogen allows plants to grow more green and grow faster.  Too much nitrogen can burn a plant or cause it to grow too quickly.  

Slower growing plants like conifers need less fertilizer than faster growing ones like annual flowers and vegetables.  Too much fertilizer, even organic types can be lost into the atmosphere or washed away if the plants don’t use it.

Always water your granular fertilizer immediately after applying to the soil.  The nitrogen in fertilizer can undergo a process by which the bacteria in the soil react with the nitrogen and release it to the air before a plant gets a chance to use it.  This is called denitrification and basically wastes your fertilizer.

The second number represents phosphorous. This nutrient helps plants build stronger roots and also bigger and more floriferous blooms.   You will see products that promote beautiful flowers often with a high middle number.

Safer® Brand’s TruBone + is a good example of this type of product with 20 percent phosphorous.  Too much  phosphorus is bad for the watershed which is why we have low or no phosphorous detergents.

Plant food with a higher middle number is great for promoting bigger blooms. (Image:Safer Brands)

Plant food with a higher middle number is great for promoting bigger blooms. Safer® Brand

This is why Safer Brand’s Lawn Restore has no phosphorous in it.

Safer Brand Lawn Restore Is Perfect For Stressed Lawns (Image:Safer® Brand)

Safer Brand Lawn Restore Is Perfect For Stressed Lawns (Image:Safer Brand)

Finally  the third number represents potash which is a good nutrient for the overall health of the plant.  It helps fight of disease. Safer® Brand makes a product called Awaken with has has a high percentage of potash.  This is good for seedlings which need to get a healthy start in life to survive.

Awaken is great for organic gardening (Image:Safer Brand)

Awaken is great for organic gardening (Image:Safer® Brand)


There are a lot of products available for amateurs and professionals to help you grow successful plants.  Whatever product(s) you choose, be sure they are made from high quality, preferably slow release organic ingredients.

Products that are synthetic can do more harm than good and can even interrupt the good bacteria and other soil microbes so vital to plant growth.