Gardening conditions at high altitudes are quite different from those at lower altitudes.  When I moved to Pine, CO in the Front Range of the Rocky Mountains, I discovered I had to change almost every gardening technique that I had used in my eastern gardens to accommodate the high altitude environment.  The following list contains some of the differences that I've observed about the high altitude conditions here at 8,150 feet:

1.  Short Growing Season.  This is an obvious high altitude attribute.  My garden is frozen until sometime in April, I have snow into May, and my last frost occurs around Memorial Day.  We can have snow here in even in July, although this is unusual.  Some years, the first hard frost occurs in August.  In November, my garden freezes solid again for the winter.

2.  Brilliant Sun Shine.  The depth of the atmosphere is shallower at high altitudes, allowing more of the sun rays to reach the ground.  The increased UV quickly heats up the air and, just as quickly, can cause a major sunburn on the unwary human.  The sun is so strong that the soil in my garden desiccates 4 inches down in just a few hours.  Plants literally dehydrate, wilting down to the ground, no matter how much I water, mulch or add organic matter to the soil.

3.  Wide Temperature Fluctuations.  In the summer, the temperature ranges from lows of between 40°f and 45°f to highs of between 85°f and 95°f.  Tomatoes and peppers won't set fruit below 50°f; lettuce and spinach dislike the higher temperatures.

4.  Lack of Top Soil.  Most of my property is forested, sloped land but not excessively steep.  Here, the top layer of soil and organic matter is only an inch or two deep before rocks and very poor subsoil appear.  This part of the Rocky Mountains has a stony soil mix called "decomposed granite".

5.  Lack of Organic Matter.  We have two beautiful meadows on our property where the soil is black and appears to be ideal for gardening.  After plowing a portion of one of the meadows for my first vegetable garden, I had the soil tested.  There were very few nutrients and no organic matter at all.  The strong sun literally burns up all organic matter in the soil.

6.  Lack of Moisture.  The air has very low humidity resulting in a high evaporation rate.  After a rainfall (or snowfall), the evaporation of moisture rising from a road surface looks like fog  Within one hour, the ground and all surfaces are completely dry again.  One of the consequences of this lack of humidity is that limbs and logs from fallen trees take more then 15 years to decompose.

7.  High Alkalinity.  My soil tested at 8.3 ph.  Not many vegetables, flowers, or fruits tolerate such a high alkalinity.  Plants are not able to use the nutrients in the soil.  Even my well water has an alkalinity of 8.0 ph.

The conditions that I described for Pine may or may not match your gardening conditions.  Hopefully, you have more favorable conditions;  you may have a harsher environment.  Gardens just a few miles apart may have vastly different growing environments.  Even the same property may have different gardening conditions just a few yards apart depending on attributes such as the direction (south, north, etc.) of the slope of the land or the amount of shade.

I did not even attempt a garden for the first two years after I moved to Colorado because I was so overwhelmed by the differences.  However, while high altitude conditions may be difficult to overcome, you can garden successfully. Before you begin gardening up here, you may want to compare your gardening conditions to mine and make your plans accordingly.