Danny's Blog: The Fertility Specialist

Fertility 101:  Getting Started

What crop am I going to grow?

Maybe it seems too obvious of a question, but asking yourself the question ‘What crops am I growing or wanting to grow?’ can go a long way in determining the fertility approach you want to take.

For instance, if you’re growing annuals, they are usually grown by using water soluble fertilizers applied through an injector system using an overhead irrigation system. Plants are usually fed on a continual schedule. Water soluble fertilizing can be controlled and managed very closely by altering the rate and type of fertilizer used  

If you're growing perennials, woody ornamentals or trees, control release fertilizers (CRF’s) are usually the dominate choice of fertilizers used. These fertilizers come in a variety of longevities and analysis'. Some larger scale nurseries supplement their CRF program with a fertigation or drip system which usually includes the use of water soluble or bulk liquid fertilizers such as UN32, ammonium nitrate or other fertilizers. Slow release or granular fertilizers are also usually used to supplement a basic fertility program.

What are my general crop cycles?

Knowing your crop cycles or schedules can be key in selecting the proper fertilizer analysis and longevity of your fertilizers. The simple principle of matching your crops growth curve with the release curve of your fertilizer is important in maximizing the efficiency of your fertilizer and minimizing your crop residency time.

The results of not matching the fertilizer release curve with your crops growth curve are a waste of valuable fertilizer, but more importantly a much longer than needed crop time. I witnessed a grower that got an additional spring crop tomarket because he used the proper length fertilizer on the short term crop.

The tricky part of this tool is to find a happy medium across all of your crops and not to complicate your fertility program beyond the management skills of your grower.

Sometimes, as a production manager, I found it helpful to draw out timelines on several of my key or complicated crops to visually see what timing or grouping opportunities the crops had to decide if they warranted a separate or alternative fertility program.

Finally, an important and overriding principle in developing your fertility program and one never to forget is KISS. ‘Keeping It Simple Stupid’ has saved many a manager from serious headaches and frustration.

Remember, have a question? Call and we can chat! If you have some topics you’d like me to discuss feel free to send me your request.

See you next month when we discuss the basic different fertilizer types and their characteristics!

Nelson Plant Food Conversion Table


I think I’m having problems with my water? By asking a few questions and looking at a recent water report, one can quickly tell if it’s something in the water or a problem in the irrigation process.

What NPK fertilizer would you recommend? That can be answered once several questions are answered pertaining to the length of the crop, type of plants grown, facility mixing capabilities, injection capabilities and irrigation systems are known.

What micronutrient package would be best to use? It will depend on water your water analysis, crop type and nutritional requirements are identified and what other fertilizers are being added to the growing media.

What fertilizer rate would you recommend? An optimum rate or range could be recommended once the crop is known, it’s balance of residency, what if any fertilizer is already in the water and when and with what was it fertilizer originally with?