If you grow flowers and/or vegetables in your garden, they need pollination in order to procreate. Much of the pollination of plants is done by bees as they move from plant to plant carrying pollen from one to another.
Having your own beehive will give you honey as well as ensure pollination of your flowers and vegetables.
Following are free plans and instruction for a number of beehives.
Plans 1 - 8
Plans 9 - 15
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Free plans - Low cost beehive plan
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Free plans - Beehive with frame plan
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Free plans - Dadanth-depth shallow beehives
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Free plans - Basic beehive
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Free plans - Langstroth beehive
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Free plans - 10 frame Langstroth beehive
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Free plans - beehive solar wax melter
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Free plans - beehive slatted bottom rack
Plans 1 - 8
Plans 9 - 15