by Mali Farnsworth

Created on: December 25, 2011   Last Updated: December 26, 2011

The germination process of the lima bean is the classic, case study of how seeds begin to grow.   

The lima bean, as all seeds and spores, contains the genetic material necessary to duplicate the plant from which it originated.  And yet the bean itself will remain dormant, that is alive but not actively growing, until it encounters three of the following conditions: light, warmth (a minimum of 65degrees is required for lima beans), and water. 

Germination is the ‘waking up’ process which takes the seed from ‘sleep’ to the state of an actively growing seedling with roots and primary leaves. 

To observe the process gather the materials below:

3 drinking glasses or clear plastic cups

5 Lima Beans

Cotton balls

Paper toweling

One Tbsp of bleach

Tap water

In one cup prepare a bath of ½ cup of water and bleach.  Place beans inside mixture and let set for ten minutes.  This will disinfect the beans, killing any unwanted mold or fungus which could rot the lima bean during the germination process.  Wash the beans with clear water then set them to soak in a second cup filled with plain tap water.  Lima beans should remain undisturbed for approximately 2-3 hours at room temperature.  (This causes the bean to swell which in turn ruptures the seed coat) 

Use this time to prepare the third cup by lining it with a ring of doubled, paper toweling.  Fill the center of the container with enough cotton balls to hold the paper towel ring in place.  Following this, plant the seeds in the third cup, slipping them between the sides of the container and the paper toweling.  Position each bean halfway between the top and bottom of the container while allowing for adequate spacing between each to eliminate crowding.  Fill with water until cotton is saturated and a small reservoir is created at the bottom of the container.  Water should be seen to dampen the paper toweling as well.

Remove the prepared cup of beans to a warm, well-lighted area.  Avoid drafts as this may lower the temperature surrounding the beans below the minimum 65 degrees.  And be sure to keep your growing lima beans moist, adding needed water before signs of dryness appear.

A small root, called the radicle, will emerge after approximately the second day while the plumule, the primary stem of the new lima bean plant, appears on or about day nine.  This crook-neck stem holds the new plant’s  first leaves.   Note the development of color pigment in the tissues. 

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