If I were to choose a season as my favorite, it would be a tough choice between fall and spring. I enjoy the fall because the garden is at its zenith and I know my winter break from most gardening chores is right around the corner. With that being said, I think I would have to choose spring as my favorite of the four. Spring brings new hope and a chance to rework parts of the garden that have been bugging me or just need to be cleaned up. Plants are coming alive: palms begin to open new fronds, cycads begin to pucker for new flushes, my hibiscus start to flower again and the sun stays out longer with each new day. It is also time to start my spring fertilizing regimen. While most people likely won’t get excited about something like this, I do, in a nerdy sort of way. There is an art to fertilizing and you should always be refining your technique or procedures. I have learned a lot about fertilizing my 1-acre garden over the last 10 years. Each year I learn a little more. Through the years I have evolved past just using cheap granular, to trying 100% organic for two years (major failure by the way), to now running fertigation with supplemental feedings. All this goes on top of my every 1-2 year mulch and/or compost additions I do to improve my nutrient-void decomposed granite (DG) soil.
The first step in starting my spring fertilizing regiment is to add water-soluble fertilizer to my EZ-Flos. EZ-Flo is a great system that delivers fertigated water through my sprinklers with each watering. Not without its flaws, it was the best choice for my yard as I couldn’t run a mainline Dosetron due to the pool autofill and koi pond spout being attached to the landscape lines. My four EZ-Flos go in after the sprinkler values. My biggest EZ-Flo hides back with my pool equipment and only takes 5 minutes to drain and fill again.
For the last two years I have used Everris Peters Excel Water Soluble Fertilizer with great success. So I will continue using a 25-pound bag for each EZ-Flo. I can get about 2-3 weeks of fertigation out of one bag depending on watering schedule. I am also adding Southern Ag’s Palm Nutritional Spray as a micro-element supplement boost for this first EZ-Flo fill only.
For me, Peters Excel 15-7-25 High Magnesium and Potassium formula is the perfect water-soluble formula for my soil and water conditions. Most appealing is that they only use high-quality sources for their nutrients. You will notice on the label below that all the minors are chelated, for example. Peters Excel dissolves fast, so it is very easy to mix and fill my EZ-Flo tanks with.
This El Niño year we saw a few large rain storms and in my decomposed granite soil heavy rains leach out potassium and most of the minor elements. By summer time I could see the effects of this in the new leaves of some of my palms. Normally I use this Southern Ag’s Palm Nutritional Spray as a foliar feed in my greenhouse. This year I figured I would try it as a way to boost Iron and Manganese – which are both in small ratios in the Peters Excel 15-7-25 water-soluble formula.
After many years of observing the plants in my garden, I noticed one consistent thing in my DG soil. That constant was that if my plants (mostly my palm trees) suffered from a nutritional deficiency, it would almost always be a potassium and/or magnesium deficiency. While not as bad as in sandy soils, in DG-based soils potassium can leach out since there is no clay or organic matter to hold the potassium ion. So on top of the high magnesium and potassium water-soluble formula I showed above from Peters, I also add SulPoMag to the base of my heavy feeding palms, all my hibiscus and my tropical flowering trees. I am a huge fan of SulPoMag and use this GreenAll 20% K and 10% Mg formula throughout the year. Unlike many rock-based fertilizers, SulPoMag is readily available to plants so it won’t need weeks or months to start feeding plants. It also won’t increase your soil pH.
In the garden, manganese deficiency typically shows itself as “frizzle top” in palms and cycads. While never a regular occurrence, it would happen in my garden to one or two palms or a cycad flush each year. Since supplementing my palms and cycads with a small amount of manganese sulfate, I have not had a single palm or cycad show “frizzle top.” Another reason I like to use manganese sulfate stems from the fact I love to grow a lot of the hard to cultivate New Caledonian plants. Many of them come from high manganese concentration ultramafic soils. I know New Caledonia is famous for its hyperaccumulators but I never really confirmed if the plants I am growing are indeed such. But what I can tell you is that my success rate with tricky New Caledonian plants increased greatly once I started supplementing them with manganese sulfate. This Greenway Biotech Manganese Sulfate bag is highly concentrated at 31% manganese, so I do not need to use a lot to get the job done. I only add this during my spring fertilizing, no other time of the year.
Lastly, I am trying something new with my spring fertilizing regiment. Well, making the old new again is more accurate. The last few years since moving to my EZ-Flo and fertigation, I stopped using a granular, broad-range fertilizer. This year I wanted to see if using a granular boost to start the spring growing season would yield any noticeable results over just using fertigation. Prior to the EZ-Flo I would use a controlled-released Nutricote formula which I was very happy with. Simply out of laziness and being cheap I didn’t drive to the speciality store and buy Nutricote. Instead, I drove around the block to my local Home Depot and bought Vigoro Palm, Ixora & Ornamental Food. A 40-pound bag was $19. A 50-pound bag of Nutricote would run me around $90! Here is our new 6-month-old puppy “Lona” modeling a bag of Vigoro.
As you can tell from the ratios shown below, it is a 8-4-8 formula. So while the percentages are low, the ratios are good. I really like to see a 2:1:3 N:P:K ratio. Most glaring to me on this cheap stuff is the origin of the nutrients. When compared to the water-soluble Peters Excel, you can read that Vigoro uses ammoniacal nitrogen and urea as their main source of nitrogen, not nitrate. Vigoro also uses potassium chloride where Peters uses potassium nitrate. Another thing that should stand out is that nothing is chelated in Vigoro. I won’t explain why all this is important in this post, but in the coming months I plan to write up a blog post detailing what to look for in fertilizers and what the advantages are when buying higher quality formulas. Just know for now that Vigoro is at Home Depot for a reason. Sure it will work fine for most people, but those discerning gardeners will notice the difference over time with what quality formulas can do.
So there you have it. This year’s spring fertilizing regimen. What you think? What do you guys do as a standard fertilizing practice each spring? Please share your thoughts in the comments section below.