Post by ogeezer on Oct 8, 2007 17:46:49 GMT -6
...was going to wait til winter to post this project but with bluex2us's querry about potting sheds on another forum, I'll post it now for her and everybody else.
Many of us who garden have learned the benefits of starting our own vegetable and flower plants. There are several benefits to having a spot to start your own plants:
First, the construction of this germination bed used in a greenhouse built for a friend living in north Texas. He has started thousands of plants in this homemade structure over the years. To get the seeds sprouted and growing, a heated germination bed was built on one of the benches in the greenhouse. It is at a convenient work height and really gets the plants going. The big advantage—and something to keep in mind when starting your plants—is that it is heated from the bottom. Regardless of how you construct your germination bed, the secret is to provide gentle heat from beneath the starting flats or trays. There are electrically heated rubber mats available, but I have not been able to justify the high prices asked for the mats offered in the growing supply catalogs. Also, being somewhat of a do-it-yourselfer, I came up with a way to go would be to make my own to fit his needs.
The heated germination bed constructed in the greenhouse is simple and works very well. It is framed on one of the greenhouse benches with some old 1 x 6 lumber. The measurements were not critical, but I did allow space for several of the black plastic seedling trays, recycled from a local grocery store, that was selling commercial plants. The accompanying illustration pretty well describes the sizing and most of the construction details.
Once the frame was built, I cut a piece of foil-backed insulation board to fit snuggly inside the frame. Any cracks were then sealed with a squirt of expandable foam insulation that is available at any hardware store.
Next, a 1/2-inch layer of clean sand was added and spread evenly over the insulation board. I then arranged a heat cable as evenly as possible on top of the sand. After it was in place, I added another layer of sand and spread it evenly over the cable.
Here’s an important note about the heat cable. The cables used in this project and those mentioned above are not the type used to keep pipes from freezing. Those would endanger the seedlings and the gardener (via electrical shock). I purchased them from a commercial grower’s supply company. They are made just for the purpose we are using them for and keep the soil at about 70° F.
Another trick I added was the covers, or lids, for the germination beds that you can see in the photo. Made with 1 x 2 stock of a convenient length, covered with a woven plastic material, used in the greenhouse project or bought at a garden supply store. They can be raised or lowered as temperatures dictate. Even in the greenhouse, the covers can help to get plants sprouted more quickly.
ADDENDUM: As you might already know, decomposing plant material can create a good amount of heat. This is especially true if the plant material has been processed through some type of livestock first! Potting soil is somewhat expensive but can be enhanced with small amount of compost, fresh livestock/poulty manure -- don't go overboard as too much will burn young plants.
As the manure decomposes, it will create steady even heat for your sprouting seeds, decreasing need for bed heating, except on really cold days/nights. It’s a good idea to keep the bed in the 75-85 degree range. A cheap outdoor thermometer will help you keep tabs on the temperature. Monitor the temperature in the bed, covering it at night and on cool cloudy days, and raising the cover during the day as conditions warrant. The sun will heat things up even on cool days, so keep an eye on it.
It is easy to “cook” young plants if they don’t get some ventilation.
Good luck on getting a head start on your seedlings.
Many of us who garden have learned the benefits of starting our own vegetable and flower plants. There are several benefits to having a spot to start your own plants:
- Getting a jump on the normal growing season.
- Not having to wait on commercial plant growers.
- Growing uncommon or unique varieties that you particularly like but are hard to find.
- Economics—once you have everything in place, you can grow your plants for little or no cost.
First, the construction of this germination bed used in a greenhouse built for a friend living in north Texas. He has started thousands of plants in this homemade structure over the years. To get the seeds sprouted and growing, a heated germination bed was built on one of the benches in the greenhouse. It is at a convenient work height and really gets the plants going. The big advantage—and something to keep in mind when starting your plants—is that it is heated from the bottom. Regardless of how you construct your germination bed, the secret is to provide gentle heat from beneath the starting flats or trays. There are electrically heated rubber mats available, but I have not been able to justify the high prices asked for the mats offered in the growing supply catalogs. Also, being somewhat of a do-it-yourselfer, I came up with a way to go would be to make my own to fit his needs.
The heated germination bed constructed in the greenhouse is simple and works very well. It is framed on one of the greenhouse benches with some old 1 x 6 lumber. The measurements were not critical, but I did allow space for several of the black plastic seedling trays, recycled from a local grocery store, that was selling commercial plants. The accompanying illustration pretty well describes the sizing and most of the construction details.
Once the frame was built, I cut a piece of foil-backed insulation board to fit snuggly inside the frame. Any cracks were then sealed with a squirt of expandable foam insulation that is available at any hardware store.
Next, a 1/2-inch layer of clean sand was added and spread evenly over the insulation board. I then arranged a heat cable as evenly as possible on top of the sand. After it was in place, I added another layer of sand and spread it evenly over the cable.
Here’s an important note about the heat cable. The cables used in this project and those mentioned above are not the type used to keep pipes from freezing. Those would endanger the seedlings and the gardener (via electrical shock). I purchased them from a commercial grower’s supply company. They are made just for the purpose we are using them for and keep the soil at about 70° F.
Another trick I added was the covers, or lids, for the germination beds that you can see in the photo. Made with 1 x 2 stock of a convenient length, covered with a woven plastic material, used in the greenhouse project or bought at a garden supply store. They can be raised or lowered as temperatures dictate. Even in the greenhouse, the covers can help to get plants sprouted more quickly.
ADDENDUM: As you might already know, decomposing plant material can create a good amount of heat. This is especially true if the plant material has been processed through some type of livestock first! Potting soil is somewhat expensive but can be enhanced with small amount of compost, fresh livestock/poulty manure -- don't go overboard as too much will burn young plants.
As the manure decomposes, it will create steady even heat for your sprouting seeds, decreasing need for bed heating, except on really cold days/nights. It’s a good idea to keep the bed in the 75-85 degree range. A cheap outdoor thermometer will help you keep tabs on the temperature. Monitor the temperature in the bed, covering it at night and on cool cloudy days, and raising the cover during the day as conditions warrant. The sun will heat things up even on cool days, so keep an eye on it.
It is easy to “cook” young plants if they don’t get some ventilation.
Good luck on getting a head start on your seedlings.