The Effects of Microwave Radiation on Plants January 1996 

    This experiment was undertaken to determine the effects of microwave radiation on plant life before maximum damage takes place.  The reason for this experiment is to determine if there are any serious effects on plants when they are exposed to different intensities of microwave radiation.
    Research of this nature is important in order to discover more resilient species of plants.  As the ozone layer thins and more Ultraviolet radiation reaches the planet's surface, hardier species of crap plants will need to be found, possibly through genetic manipulation of existing species.  When the effects of radiation on a species are known then scientists can go about altering that species to allow it to survive.


    If plants can withstand small amounts of everyday radiation then slightly intensifying the doses should have little or no effect as well.  As well, extended periods of low intensity microwaves should have no ill effects.

Materials / Methods


  • 7 Styrofoam (or Plastic) Cups
  • Newspapers
  • Grass Seeds
  • A Spoon
  • 18 to 21 Small Rocks
  • Masking Tape
  • Soil (approx. 2100 mL)
  • Microscope
  • Measuring Cup
  • Paper Towels
  • Microwave Capable of different Power Settings
  1. Layout newspaper over work area.
  2. Place 2-3 small rocks in the bottom of each cup from drainage.
  3. Spoon approx. 300 ml of soil into each cup.
  4. Sprinkle a handful of grass seeds into each cup - Be Generous.
  5. Cover seeds with another spoonful of dirt.
  6. Water with 25 ml of water.
  7. Place in indirect sunlight for 7 days watering with 25 ml of water every second day.
  8. On Day 8 remove plants from the window and label each plant with masking tape writing on tag plant number, power level, and time in microwave.  The power settings are 1, 3, 5, 7, and 9 for one minute and power level 1 for 3 minutes.  The extra plant will be kept as a control.
  9. Microwave the plants according to their tags.  Record what you see after each plant has been microwaved.  When finished place back into sunlight.
  10. After two hours has passed give each plant 25 ml of water.  Continue to water each plant with 25 ml of water every second day.
  11. After seven more days remove plants from window.
  12. Layout new newspapers in the work area.
  13. Dig up a sample of each plant recording what you observe in each plant (i.e.: Soil Texture, Moisture).
  14. View each sample under the microscope.  Record what you observe.
  15. Compare the findings for each plant with the findings for the Control plant.

Results / Observations

    The plants grew normally for the first seven days.  There were no notable abnormalities.  After being microwaved each plant displayed its own new set of characteristics.  The plants that were microwaved at lower frequencies showed limp leaves as well as gave off a slight odour.  Those microwaved at higher frequencies showed more drastic changes such as wilting of leaves, heating of leaves, and strong lingering "earthy" smell.  The cups of those plants microwaved at higher frequencies also heated up.  The effects of this heating did not appear until days later when the plants quit absorbing water from the soil.  The daily water was just absorbed into the soil until the plants began to rot in a puddle of mud.  When the plants were unearthed this could be attributed to the virtual absence of root hairs on the plants.  These plants as well had no food storage nodules on the roots and it can be said that these plants died only after exhausting their own food supplies.  Some ungerminated seeds discovered in the soil had some discoloration.
Time in Microwave 
(in minutes)
Plant 1
Plant 2 Plant 3 Plant 4 Plant 5 Plant 6 Plant 7
0:00 Roots fully formed with Root hairs and nodules.  Healthy Green Colour.            
1:00   No Root hairs for up to 1/2 cm before Root tip.  Healthy green colour.  Soil is damp.  Few Nodules on roots. Soil is damp with excess water.  1 full sized root hair.  No root nodules. Some dead grass at outer edge.  Soil is wet.  Very small root hairs, hardly visible.  Light "earthy" smell. Much excess water.  No root hairs.  Some leaves bleached white with no chlorophyll.  Strong "earthy" smell. Plant is Dead.
Mould growing amongst the leaves.  Much excess water.  No root hairs.  Very strong smell.
3:00             Appears to be healthy.  Few Root Hairs.  Soil is damp.

    The plants that were microwaved at lower frequencies showed no such extremes.  The plant irradiated at level five showed little root hair loss but did experience some dying off in the outer blades.  Because of the root hair loss it too showed higher moisture content in the soil.  The plants microwaved at levels one and three showed no detrimental effects of their experiences and in fact began to grow better after being irradiated. They had no root hair loss and no dying or browning of the leaves.
    The seventh and last plant was microwaved at level one for three minutes to show that extended periods of low level radiation also had no ill effects on plants.  It, too, experienced improved growth after being irradiated.  It experienced no root hair loss or browning of leaves.


    The largest and most noticeable error in this experiment is that the plants were irradiated in small cups and that this created an extra, added entry point for radiation.  It is true that being heated in their cups may have caused damage to the more exposed roots than would be experienced in the outdoors, but no matter how good of a shield the ground would be, the most extensively used crops have shallow root systems not unlike the grass used in this experiment.
    Another error may have occurred when the plants were unearthed for closer observations.  It may have been that the high temperatures only caused the root hairs to become extremely fragile and the process of removing them from the soil damaged them further.  This is probably not the case because the plants appeared to be dying as much as three days before being unearthed.

    In this day and age of global and environmental awareness this project shows some startling consequences to the thinning of the ozone.  If the radiation that reached Earth were to increase ever so slightly we may find ourselves inside an atmosphere not unlike the microwave on Power 5 or higher.  WHile no immediate ill effects were shown (within one week) on the power five plants what would they ultimately be like after two weeks or two months?  Maybe the short term burst of radiation harmed their genetic structure making them sterile or causing defects in their offspring.  And long term radiation, longer than three minutes, would almost certainly have some sort of ill effect on the plants.  It would be interesting to try this experiment and substitute the grass seeds for vegetable seeds or tree seeds.  In the case of the vegetables would the radiation change their taste of coloration?  Would the trees be stunted, destined to be warped, skinny versions of their former selves?  What would be the effect of microwaves on unplanted, ungerminated seeds if they were irradiated and then planted to grow?  Would the seeds grow to be stunted, smaller plants?  Or would they germinate at all?  These questions must be answered before it becomes too late and mankind is stuck on a dying planet with nothing to feed himself with.