This is an activity that can be done individually or in pairs. It generates a great deal of interest and surprise as well as friendly competition, but make sure that everyone has the same materials to make it fair.
Pre-soak the beans in tepid water for 24 hours (four for each person and a few spares if you're doing the full experiment below)
Find some jars - finish that jam quick!
What to do
Ensure every person (or pair) has four presoaked beans.
Take one square of kitchen towel and fold it in half. Curl it around so that it forms a tube, and put this into the glass jar. The kitchen towel tube should stand up and ‘line’ the jar (all the way around).
Take another piece of kitchen towel and scrunch it up loosely. Stuff it gently into the kitchen towel tube to ‘pack it out’ against the glass wall of the jar. Repeat this until the tube is ‘full’ of kitchen towel.
Take two pre-soaked beans and leave them as they are. These are your ‘Complete’ beans. Take two more beans and carefully ‘peel’ them with your fingers i.e. remove the seed coat but make sure the rest of the bean stays intact. These are the ‘Naked’ beans! Split one of the Naked beans in half i.e. remove one food-store organ (cotyledons) and discard it.
Summary – Each person (pair) should now have two Complete beans and two Naked beans. One of the Naked beans should be only half a bean.
Now arrange the four beans around the jar so that they are jammed in between the glass wall of the jar and the tube of kitchen towel. (See instruction 7 below).
N.B. Beans should NOT be planted on the scrunched up kitchen towel in the middle – this is a common error! Beans should be about half-way up the jar. They must not touch the floor of the jar. If they do, use the dibber to drag them out and start again.
‘Plant’ your beans as follows:
a) One Complete bean planted the right way up (the little 'mouth' at the top - this is where the plant will sprout)b) One Complete bean planted upside-down (mouth downwards)c) One Naked bean planted the right way up) One Naked half-bean planted any way you choose!
Write your name and the date on the sticky label and stick it under the glass jar.
Carefully add some water to the jar so that there is 1cm depth in the bottom of the jar.
N.B. make sure that no bean is in the water.
The kitchen towel will soak up the water and the beans will stay moist.
Put the jars in a warm place (18 to 24°C is ideal), and wait to see what happens for about three weeks. A warm windowsill will do.
You need to ensure that there is always 1cm depth of water in the jars and that all jars are treated ‘equally’. As the green shoots develop, the jars will need to be kept in the daylight.
Good results are obtained using green Broad beans such as ‘The Sutton’, a dwarf variety (30cm) or ‘Aquadulce Claudia’ which would normally grow to one metre. Avoid the red skinned ones e.g. ‘Red Epicure’, as they tend to ‘leak’ the red dye all over the kitchen towel, grow slowly and are prone to rotting.
To make it a fair competition, use the same variety of bean for everyone. Dwarf bean ‘The Sutton’ is easier to transport if you are going to take the jars away each week. If you want to introduce a bit more fun into the competition, mix together some tallbean seeds with the dwarf ones before you soak them!
The anticipation and interest increase if the jars are taken away at the end of the first session and someone looks after the jars for the week.
The jars are then presented a week later and passed around so that everyone can choose a ‘winner of the week’. This often prompts good discussion and encourages observations as people discuss and decide who the winner is; is it the tallest bean so far, is it all the beans together? Do you include the roots? Do this for three weeks.
In the second (final) week remove the beans from the jars and measure them from top to toe (tallest shoot tip to longest root tip). There are always surprises!
The beans develop at different rates; some will fail completely. The root grows first to act as an anchor. Any rotten or mouldy beans should be removed. The beans that were planted upside down ‘sort themselves out’ as the shoot curls around and starts to grow upwards and the root curls around and starts to grow downwards.
The removal of the seed coat in the Naked beans often makes a surprising difference, and the half-beans may do extremely well at first but then slow down as they run out of food. If beans are grown for longer than three weeks some will develop flowers and pods. They need liquid fertiliser e.g. Tomato fertiliser to help them do this.
If you get very attached to your beans - plant them out in the garden if you can and see if you can get some return on your little magic bean!