Step 3: Set temperature & insert heater

The temperature for germination varies form plant to plant but you can find a good guide to seed germination temperatures here.
For tomatoes we set it to 26 degrees C (78.8 degrees Fahrenheit).
Then place the heater on the bottom of the box with the suction cups facing down.
<p>Hi</p><p>It is interesting, I would like to make one.</p><p>any idea how to get the instruction to make it?</p>
<p>I like the way that this solves moisture, humidity, heat, and most difficult- temperature control, with the use of something as cheap as an aquarium heater. this is definitely the way I am going to go. I've seen something similar using a large, insulated enclosure with seed trays in it, and a pan of water at the bottom with a thermostatic heater in.</p>
What are the brown rocks on top of the perlite surrounding the seeds in the images of the last step?
very good guide i like it... <br>Thank you
very good guide i like it... <br>Thank you
Hey! Thanks a lot! I will be doing a desing practice on biology lab about germination soon and decided to use temperature as the variable but i was struggling on how to control de temperature.. GENIOUS! After planting the seeds you just water them on top.. right? Thanks (:
Hey, good luck with that I hope it turns out well for you! Watering them after they have been planted is a good idea so the root system has a chance to establish. Keep me posted on how it went.
Sorry bit lengthy - but to clear it up for all- have a great day What is perlite? Perlite is a naturally occurring siliceous volcanic rock. The distinguishing feature which sets perlite apart from other volcanic glasses is that when heated to a suitable point in its softening range it expands twenty times its original volume or more. This expansion is due to the presence of 2% to 6% combined water in the crude perlite rock. The water became entrapped into the amorphous material on instant cooling after an eruption. When quickly heated above 870ºC the crude rock pops in a manner similar to popcorn. As the combined water vaporises, it creates countless tiny bubbles in the heat softened glassy particles. It is these tiny glass-sealed bubbles which account for the amazing light weight and other exceptional physical properties of expanded perlite. The expansion process also creates one of perlite's most distinguishing characteristics - its white colour. While the crude rock may range from transparent light grey to glossy black, the colour of expanded perlite ranges from snowy white to greyish white. Typical Physical Characteristics Colour: White Refractive Index: 1.5 Maximum Free moisture: 0.5% Specific Gravity: 2.2 - 2.4 Softening point: 870 - 1093ºC Fusion point: 1260 - 1343ºC Specific Heat: 837 J/kg Typical Chemical Analysis Weight % Silicon oxide (SiO2): 76,2 Aluminium oxide (Al2O3): 12,1 Potassium oxide (K2O): 4,9 Sodium oxide (Na2O): 3,4 Iron oxide (Fe2O3): 0,7 Calcium oxide (CaO): 0,6 Magnesium oxide (MgO): 0,1 Manganese oxide (MnO): 0,1 Titanium oxide (TiO2): 0,1 Loss on ignition: 1,9
Thanks for clearing that up. I've always wondered where they actually get the silica from. (seriously) BTW no matter where it comes from it WORKS! I had seeds sprouting within 4 days!! Take care, Moderator
"WARNING: Perlite is made of silica, DO NOT breath in the dust!" Huh? I though perlite was made out of volcanic rock. Or it may be my mistake that volcanic rock is silica?
Perlite is silica which is heated under pressure until it pops like popcorn. You may be thinking about <a rel="nofollow" href="http://en.wikipedia.org/wiki/Scoria">scoria</a> which is made form volcanic rock.<br/>
I believe you may be thinking of pumice.

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