Avocados are a southern plant, which I am sure you know. But in most varities require a 'mate'. So you will need to have at least one more to properly germinate.
As far growing it, keep in mind that most of the Avocados in the world are grown in Mexico, So California, and the southern climates. You can not let the roots freeze. You can grow an Avocado from the pit by putting toothpicks into the middle of it and soaking one end in a glass or cup of water. Keep the water full. In a few weeks you will see a shoot. When the shoot gets bigger, you can then plant it into a pot. Just keep it warm.
Hope this helps

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Avocados are a southern plant, which I am sure you know. But in most varities require a 'mate'. So you will need to have at least one more to properly germinate.
As far growing it, keep in mind that most of the Avocados in the world are grown in Mexico, So California, and the southern climates. You can not let the roots freeze. You can grow an Avocado from the pit by putting toothpicks into the middle of it and soaking one end in a glass or cup of water. Keep the water full. In a few weeks you will see a shoot. When the shoot gets bigger, you can then plant it into a pot. Just keep it warm.
Hope this helps

Wow, harvesting fresh avocados would be great, that sounds like a fun project. Especially with a greenhouse. What kind are you thinking of getting eventually? Freestanding, or attached to the house?