How to choose the right fertilizer for home vegetable gardens

Trips to the local garden center can be a bit overwhelming when trying to decide what fertilizer is best for your home vegetable garden.

With a bit of knowledge about the fruits and vegetables you’re planning to grow and understanding what your goals are for your garden, these tips from Texas A&M AgriLife Extension Service horticulture expert Lisa Whittlesey can help you make the best plan for your home garden.

Knowing which vegetables you want to grow and what nutritional requirements those vegetables have is key to picking out the fertilizer best suited for your garden.

Plants require light from the sun, moisture from rainfall or irrigation, and nutrients from fertilizers, compost or manure. An adequate amount of all three will help get your garden off to a good start.

Types of fertilizer

There are many types of fertilizer, including organic, non-organic, water-soluble and slow-release fertilizers.

“Gardeners often choose these based on personal preference,” Whittlesey said. “Organic is great for working into the soil, while granular fertilizers can be used during planting, and liquids are good for transplants.”

“It is important to remember that plants require nutrients, or fertilizer, to do well,” she said. “And plants don’t care where their fertilizer comes from, whether it is organic or traditional. As long as the nutrient requirement is met, the plant will thrive and do well in your garden.”

Fertilizer labels N-P-K

There are three numbers located on each bag, representing the amount of nitrogen, phosphorous and potassium in that particular fertilizer. A complete fertilizer will include all three components.

“If you are gardening in an area you haven’t gardened before, a soil test might be a good indicator of what your soil really needs,” she said. “Some nutrients, especially phosphorous, stay in the soil longer, while things like nitrogen tend to not stay in the soil as long. A soil test will tell you existing levels of all nutrients and will give gardeners recommendations of what to add. You may, or may not, need a complete fertilizer, depending on your existing soil nutrient levels.”

All parts of a plant can benefit from nitrogen, including the roots, leaves, stems, flowers and fruits, and it also provides plants with their green color. If the leaves begin to yellow or the whole plant turns pale green, a lack of nitrogen may be the reason.

But beware, too much nitrogen may kill your plants. It is also important to not use lawn fertilizers in your garden, as they contain too much nitrogen and may injure vegetables.

While phosphorus is needed to help form roots, flowers and fruit, a phosphorus deficiency causes stunted growth and poor flowering and fruiting.

Plants benefit from potassium in many ways, and a potassium shortage may be visible in stunted growth and yellowish lower leaves.

“Typically, your leafier greens and lettuces will benefit from a higher amount of nitrogen, and the vegetables that you may be harvesting fruit from may require a higher amount of phosphorous and potassium,” she said.

If you are unsure whether or not you need a fertilizer, grab a soil test for your garden or visit AgriLife Extension for more information on fertilizing your garden.