The Submersible Pump
A Quick and Easy Way to Fertilize a Large Rose Garden

By Kitty Belendez

When I first started growing roses and only had a dozen plants, I used a dry granular fertilizer, which only required that I sprinkle 1/4 cup around each bush, and then water it in afterwards. This particular granular also included a systemic insecticide. This method was easy enough for monthly feeding of just a few bushes, but after a few years when I had accumulated over 50 bushes, the granular fertilizer was becoming too expensive to use. And I did not like putting all that insecticide into the soil every time I fed my roses. I wondered what it was doing to the worm population.

Then I discovered the water soluble fertilizers and liquid organic fertilizers such as fish emulsion. These were less expensive and faster acting than the granular, but I had to mix them one tablespoon per gallon of water and carry one bucket at a time around to each rose bush. It didn't take long to find out that this method of feeding 50 roses was A LOT OF WORK! In fact, all this lifting and carrying eventually caused an injury that required me to have major surgery.

Soon, I heard about the siphon device (Siphonex). This $10 device attaches to your faucet, with a tube that extends down to a bucketful of fertilizer that has been mixed at a 16:1 ratio. You then attach your garden hose to the siphon device, and when you turn on the water the concentrated fertilizer is then supposedly sucked up and delivered to your roses at the correct concentration. This method worked pretty well until I had collected over 100 rose bushes. However, the siphon had a tendency to get clogged up whenever I used fish emulsion, and I had to make sure that the device was thoroughly cleaned out after each use. Also, I was never really convinced that the device was always delivering the correct ratio of fertilizer to my roses, since I have a very high water pressure (everybody's is different), and the water pressure would drop drastically as the device would start to clog up. I finally got fed up when I just could not keep the device unclogged, even though my husband Bob frequently took it apart and cleaned out the siphon hole with a tiny needle. 

A few years later, I suddenly found myself with 350 rose bushes. I had gotten frustrated whenever I tried to feed my roses using the siphon device and had to fight with it all the time to keep it free flowing. Then around 1995 I heard that some rosarians were using a submersible pump (also known as a "sump pump"). This is the same kind of pump one would use to empty out a swimming pool, pond, or a flooded basement. This pump sounded intriguing, and for $60 (in 2015 they now cost about $80) I decided I would give it a try. I had heard that it was a real timesaver, and with 350 roses I surely needed to save some time.

Originally, we purchased our submersible pump from Home Depot. It was the 1/6 horsepower Flotec brand, model number FPOS1300-03, and is rated to pump 1300 gallons per hour. There are other brands and pump sizes available. That first pump lasted 18 years. Since then we have bought a 1/4 horsepower pump that dispenses quicker, at 1600 gallons per hour. The 1/4 HP model we now use is Flotec FPOS1775A. We bought it at Home Depot September 2012 and it cost $145.00 at that time. The 1/4 HP pump dispenses liquid fertilizer much quicker than the 1/6 HP pump. Since we have a large garden with 300 roses, it was well worth the extra money to go with the faster pump.

Link to Video Showing How to Fertilize with the Submersible Pump

To feed your roses with the submersible pump, you mix up the water soluble fertilizers at the appropriate ratio, according to the directions on the package, in a 30- or 50-gallon can. So, for example, in a 30-gallon can, you will mix 30 tablespoons of a water soluble fertilizer or fish emulsion with 30 gallons of water in the can. A friend gave us a huge plastic 55-gallon drum that we are now using. We need to fill up this drum four times to feed all of our 300 roses (more than half are minis). 

The pump is electric and so must be plugged into an electrical outlet. We use an outlet in our garage, and since the cord on my pump is short, we also need to use an extension cord. Some brands have longer cords. Before using the pump for the very first time, do a "count test" to determine how many seconds it takes to fill up a one gallon bucket. For example, I count to 8 (12 for large established bushes), which is how long it takes for the pump to dispense one gallon of fertilizer to my hybrid teas, and count to 4 for a half-gallon (or 2 for a quart) to be dispensed to the miniature roses. 

You will need two hoses: one connected to the water source for filling up the large container mixed with fertilizer, and a second hose that attaches to the pump for dispensing the fertilizer. Depending on the size of your yard, you may need to use a long garden hose to reach all your roses. The pump is lowered into the large container, plugged in to turn it on, and then you will use the hose to dispense the fertilizer. I recommend that you attach a water wand (a shower head nozzle on a long handle) on the end of the hose to prevent splashing as the liquid fertilizer is pumped through the hose. 

Before you fill up the large can, be sure you have placed it in a convenient location in your rose garden, where the hose will reach all areas to be fertilized. If you need to move the 30- or 50-gallon container around the yard, a low garden cart can be very useful.

The submersible pump is an incredible time and work saver if you have more than 100 rose bushes. It takes us just one hour to feed all of our 300 roses. It was taking me at least twice that long with other methods. We use the pump to dispense water soluble fertilizers, fish emulsion, liquid seaweed, powdered chelated iron, and even epsom salts, with no clogging problems whatsoever. Every time I use the pump, I marvel at its efficiency!

Link to Video Showing How to Fertilize with the Submersible Pump

© Copyright Kitty Belendez. All rights reserved.

This article was originally published in "Rose Ecstasy," bulletin of Santa Clarita Valley Rose Society, Kitty Belendez, Editor.

Photos © Copyright by Kitty Belendez

For questions about Santa Clarita Valley Rose Society, contact:
Kitty Belendez


Updated January 4, 2016

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