Comparison of three different watering regimes for Parsley

On 25th February, in an on-line forum I read (one of several for owners where I have my home in Spain) I saw a link to a rather alarmist (and potentially alarming) story about the alleged dangers inherent in using a micro-wave for heating or cooking food and this prompted me to write three tweets as follows:

First tweet here Is cooking in a #microwave safe? I always thought so, but since reading about it, now I'm not so sure. Just search internet for the dangers.

- in response I got a couple of responses from Twitter acquaintances, prompting a further two tweets:

Second tweet here @seafrontbloke @SeanLXIV May be all nonsense but take a look at this usahitman.com/microwave-test/

and:

Third tweet here @seafrontbloke @SeanLXIV I'm going to do my own experiment with 3 tubs of cress -1 tap water, 2 cooled m'wave water, 3 cooled boiled water

- after writing that third tweet I went out to visit my local main supermarket, with the intention of buying three tubs of growing cress, having often bought it there before - I like to sprinkle cut cress over salads and certain cooked fish - with the intention of running my own experiment. In the event, the supermarket that day had only two tubs of cress left, so I drove to a nearby town and in one supermarket there bought three quite large pots of healthy-looking growing flat-leaf parsley, very similar in growth and general vigour to my eye and thought, well, I'll try it with these instead.

When I got home a little later I thought the plants looked pretty healthy and although the soil wasn't 'dry' I thought they probably needed some water fairly soon, but that it would do them no harm to wait several hours until I had prepared the different 'types' of water.

Methodology:
- For the 'micro-waved' water, I boiled tap water as hot as I could get it in the micro-wave in a ceramic mug and transferred the resultant boiled water to another ceramic mug, covered it with a saucer and let it rest about 6 hours so that it reached room temperature;
- For the 'boiled' water, I boiled tap water in my electric kettle (made of stainless steel with a concealed element), filled a ceramic mug with the boiled water, covered it with a saucer and let it rest about 6 hours so that it reached room temperature;
- For the 'tap water', I filled a ceramic mug with tap water, covered it with a saucer and let it rest about 6 hours so that it reached room temperature.

I watered each plant with exactly the same quantity of water on each occasion, using for the purpose either a stainless steel 1/4 cup measure, or a stainless steel 1 tablespoon measuring spoon (I have a set of American-style measuring cups and a set of measuring spoons, both made of stainless steel) and I dried/cleaned each utensil before and after watering each plant. On the first evening, each plant was given 2x 1/4 cups of water, because as I wrote earlier I thought they probably needed it. After that I watered each plant mostly once a day in the morning, or occasionally a second watering took place late in the afternoon - usually one 1/4 cup each or 1 or 2 tablespoons each, depending on what I thought they needed. In all cases each plant was given exactly the same quantity of water.

For the first 4 days, the plants were kept in a place (a corner of my kitchen) where although they had plenty of light it was mainly from vertically above (a skylight) and rotated twice a day to try and ensure they received similar levels of light. However, by day 4 I began to think they were becoming somewhat etiolated, so I moved them to another room, a spare bedroom, where they had a much larger window which receives much more of whatever light and sun is available in these northern latitudes and it so happens that for the past several days we have had bright and sunny days and although pretty cold out of doors, my apartment is very effectively centrally-heated, again each plant was rotated twice a day to try and ensure very similar light levels for each plant.

You will perhaps notice that in the photographs on days 5 and 7, the 'micro-wave' plant is looking rather bedraggled, with the 'kettle' plant only a little better, but with the 'tap water' plant looking somewhat better. However by day 9 all three plants seemed to be healthier-looking and much more similar in growth and by day 11 (today) all three were to my eyes very similar. It was also very noticeable that all plants were using more water - that is to say, excess water was not quickly draining through onto the plate on which each plant-pot rested and the increased levels of light now available to them made them after a few days all look rather healthier and much more equal in growth and general health than on days 5 and 7.

My general conclusion is that the experiment linked to in my second tweet above is a load of alarmist baloney. Interestingly enough, one of the comments in the second tweet above links to another experiment which draws much the same conclusions as my own experiment.

I mentioned in a fourth tweet the following:

See it here @SeanLXIV @seafrontbloke LOL - but I'll post results with photos in 10 or 11 days. Meantime I won't be using my microwave. No hardship.

- so this article is the result of my experiment, as promised, into this supposed phenomenon. Suffice to say I will, from tomorrow, be using my micro-wave oven again to cook certain foods when I feel like it - I have micro-wave steamers which I have often used to cook/steam vegetables and fish and even occasionally chicken. I have tried it on one occasion with steak - rib-eye, my favourite cut - but that was NOT a success. Below are the photographs taken during my experiment with, in each photograph, the plants being the 'micro-wave' at left, the 'kettle' in the middle and the 'tap water' at the right. Larger images are available to view by clicking on the links below. Judge for yourself. You will notice that in the later photographs all three plants look somewhat 'yellower' and less intensely green - my conclusion is that when I bought the plants in the supermarket, they will have been grown under ideal commercial conditions, using most probably artificial light of a wavelength closely duplicating optimum sunlight, whereas after a few days in my dubious 'care' the poor plants had to content themselves with the natural light available at a latitude/longitude (57° 35' 0" N / 3° 52' 0" W) of the northern Scottish town of Nairn in late-winter. The photographs below were all taken in exactly the same position in another corner of my kitchen under as similar lighting conditions as I could manage to achieve:

Comparison of three different watering regimes for Parsley (25 February - 6 March 2012) Click here to see enlargements of all these photographs. Day 1 - 25 February 2012 - start of experiment Day 3 - 27 February 2012 Day 5 - 29 February 2012 Day 7 - 2 March 2012 Day 9 - 4 March 2012 Day 11 - 6 March 2012 - end of experiment Click here to see enlargements of all these photographs.