Types of plant propagation structures
To propagate plants you will need propagation beds. Propagation beds are nothing more than a bed of sand or other rooting media that is used specifically to propagate plants. These structures can be loosely broken down into a few categories:
- Misting Beds
- Cold Frames
Misting beds, coldframes and hotbeds are what most individuals will start off with when propagating plants. Some will have the pleasure of owning a greenhouse, but this article will not address greenhouse propagation.
For greenhouse growing I recommend the following:
How to Build Your Own Greenhouse
Greenhouse Gardener’s Companion, Revised: Growing Food & Flowers in Your Greenhouse or Sunspace
Greenhouse Gardening: Step by Step to Growing Success (Crowood Gardening Guides)
What is a misting bed?
A misting bed is a bed that has a misting system installed to keep the cuttings moist and cool.
What is a coldframe?
A cold frame is basically a box that holds your rooting media and has no means of producing or retaining heat to aid the rooting of the cuttings. Moisture is added to the soil and the cover of the frame keeps the moisture from evaporating too quickly.
What is a hotbed?
A hot bed is nothing more than a coldframe with bottom heat. The bottom heat aids in the cuttings ability to form roots. Moisture is added to the soil and the cover of the frame keeps the moisture from evaporating too quickly.
How are these propagation beds made?
There are many ways to build your propagation beds, too many to actually cover. However, I will give you a basic layout that you can use or adapt for your particular application. These beds should be made from good sturdy lumber to ensure years of service.
Here is a diagram of a simple propagation bed that uses mist to keep the cuttings cool and moist. The sides should be 6 to 8 inches high. The bed can be any length you choose, but a 4 foot width has been found to be the most manageable.
If creating a coldframe, simply make the sides taper and make a cover of glass or plexiglass to help keep moisture and heat in. The height in the back should be between 20 and 24 inches high, and the front between 10 and 12 inches high. Most coldframes are square, and a good size is 6 feet by 6 feet. To help save money and keep the cover from being to heavy, it can be cut into two pieces.
If creating the hotbed, build it just like the coldframe, but you must place heating cables below the propagating media to warm the soil to help the roots to form quicker. It is advisable to have a 2 inch layer of vermiculite below the soil warming cables to help radiate the heat upwards and insulate the propagation media from the soil underneath. You must add 1 inch of rooting medium above the cables and place a piece of wire mesh on top of the medium to ensure you do not cut into the soil warming cables while digging out your plants. As stated above, to help save money and keep the cover from being to heavy, it can be cut into two pieces.
Regardless of which type of bed you construct, each bed is filled with the rooting media to a depth between 4 to 6 inches. This can be sand or a mixture of peat/perlite.
For more information on building propagation beds, try:
Gardening Indoors and Under Glass (Large Print Edition): A Practical Guide to the Planting, Care and Propagation of House Plants, and to the Construction … of Hotbed, Coldframe and Small Greenhouse
Hartmann and Kester’s Plant Propagation: Principles and Practices (7th Edition)
Coldframe and hotbed information can also be found in the members area. Become a member today, it’s free!