sparklythings

One of my garden resolutions for this year is to not go willy nilly buying random plants. Last year was my first full year with a yard, and i knew it was going to be experimental. This year I want to pick a few key areas and really focus on those and make them look good. First on the list, as always, are the hydrangeas.

I planted four Endless Summers last January and they bloomed beautifully, perfect blues developing into purples, which I loved. But they didn’t stop at purple – the late season blooms were full-on pink!

This couldn’t be right. I had spoken to a very authoritative-sounding older southern woman at a well-regarded nursery who said if I planted hydrangeas near a pine tree they would be blue. Pine trees == acidic soil == blue hydrangeas, end of story. The Endless Summers start about 12 feet away- not exactly under the pine, but certainly close enough, right? They were well within the pine needle drop zone.

So I mulched those suckers with pine needles. Every weekend last fall I raked up two or more wheelbarrow loads of needles and they went directly on the hydrangeas – all the hydrangeas, not just the Endless Summers. I’m talking 6 inches worth of pine needle mulch here. I wasn’t going to have pink blooms if i could help it!

In the spirit of “Doing It Right” (and dealing with its cousin  “What Can I Do While It’s Still Too Cold To Plant Anything?”) I decided to actually test the pH level of the soil in that area. Duh! Then I’d know exactly what I was dealing with and what i needed to do to fix it. I stopped by Lowe’s and was confronted with my first dilemma:

There were two kinds of testers, both by Ferry-Morse: a battery-operated tester for $20 and a chemical kit for $4. I ran through the pros and cons:

Electronic Tester:

• Good for multiple uses
• Gives numerical readings instead of colors

Chemical Kit:

• Lower cost – it’s not like I’m going to start a pH testing business necessitating an electronic tester
• Seperate tests for Nitrogen, Phosphorous, and Potassium; the electronic one grouped all these into one Goldilocks reading (too much, too little, just right)
• all the tubes and colors and stuff looked way cooler

In the end I realized I had no idea which method was more reliable, so I decided to approach it like a science project and bought one of each. In the interest of full disclosure, I HATED doing science projects in high school and in fact faked the one I did about parachutes (sorry Mr. Sweetsir.) But I thought this would be fun, mostly because of the aforementioned colored tubes and stuff.

Problem:

My damn hydrangeas are pink!!!

Research:

I can never remember which way the pH scale goes, so I amended the wikimedia chart as it relates to hydrangeas (extra credit!)

Also read that all that pine needle mulch might have been wasted effort – other than being good root protection during freezes and heat waves, and at zero cost – as that pine/acid soil story appears to be a myth. Whoops.

Materials:

Dr. Funkenstein’s lab. The electronic kit requires 2 cups of soil and 2 cups of distilled water. The chemical test requires 5:1 water to soil; I went with a quarter-cup of soil and 1-1/4 cups of water. The bowl worked well for the chemical kit, but you need something tall like a cup for the electronic, as the probes should be completely covered with soil.

Procedure:

1. Read all the directions. That’s good for anything, really. And both sets of directions came with a nice explanation of the pH scale and how it relates to gardening, and what you can do to change the pH of your soil.

2. Collect your soil. You can actually use the probe directly in the ground, but the instructions said that you get more accurate results if you do it lab-style. You’re supposed to bypass the first two inches of soil, dig a hole 5 more inches deep and mix the soil up a bit. Discard rocks, twigs, and other non-dirt items.

3. Electronic tester:

mix two cups of water with two cups of soil, let it settle, then drain off the excess water. It should be good and muddy. Flip the switch to the reading you want to take, insert probe, and let sit for a minute.

4. Chemical kit, pH:

Fill tube with appropriate level of soil, then contents of capsule, then top off with water.Shake and let sit. Pause for a moment and feel like awesome scientist.

5. Chemical kit, fertilizers:

mix up your 5:1 water/soil mix and let settle. Fill tube to marked level with the water only, not the dirt (interesting!) Add capsule contents, shake to mix. I did these one at a time so I wouldn’t the tubes all mixed up. Compare color results with chart.

Data:

Discussion:

I started off using the battery that came with the meter, but since the needle barely moved I decided to try a fresh battery. The second battery produced the same results as the first – I’d call that a 6.8. The fertilizer reading was right in the middle of “Too Little.” Oh dear. Surely this must be wrong – onto the chemical tests!

Nope, that’s a very neutral green in the pH tube. Nitrogen didn’t even turn colors at all, let alone a shade of pink! Phosphorous was similarly missing, and the Potassium was only a slight shade of orange.

Conclusion:

My soil is hosed! The two kinds of pH test kits do produce similar results. My impression is that you’d use the electronic tester for mostly monitoring. If you got a bad reading on that, then you might want to pick up a chemical kit to see exactly where the problems are, so you know what to add to your soil to correct them.

I suppose if i really wanted to get an accurate reading, I could take the soil into the Extension Office and have them to a professional test. But this is good enough for now – I have plenty of other work to do!

Bibliography:

Changing the Color of Hydrangeas, hydrangeashydrangeas.com

French Hydrangea for Gardens in North and Central Florida, UF Extension

Hydrangea Questions and Answers, United States National Arboretum

This entry was posted on Monday, February 1st, 2010 at 6:30 am and is filed under gardening. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.