Does anyone have another solution I really prefer sticking with outdoor growing
Ok, your elevation shouldn't have too much of a negative effect on the plant. How much direct sunlight per day is it getting? How cold are the nights?
Excessive heat or cold will definitely slow down growth. 20C highs are fine, start getting up around 28C-30C, that may be problematic IF the roots are also getting too warm (or, conversely, too cold).
It should be receiving a minimum of about 5 hours direct sunlight per day. As a very young seedling, I've found it's impossible to overwater. In fact, click my signature line, that will take you to my gallery (that needs updating, I admit), where you will see how I start my seedlings off. I always keep their feet wet by putting them in a tray and keeping water in the tray. It is a never-fail system for me.
In general we don't want to fertilize seedlings until about 3 weeks of age. However, I've had some seeds that just didn't have enough energy on their own, a VERY mild dose of fertilizer, assuming your soil does not already have them in it, may be helpful for those individuals.
Also, Google Mycorrhizae. They are types of fungi that essentially do two things; First, they encourage growth of hair-fine roots, these are the roots with which the plant takes up nutrients. Second, they seem to act as tiny little "chelating agents" (hehheh, agents of chelation), in that they make the nutrients already present more "bio-available" for the plant. In other words, they're like your mom cutting up your food into pieces for you. Or my mom making pureed foods for the old people who have no teeth, so they can eat. Make sense? Mycorrhizae are well documented for their efficacy, too, so this is well-supported agriculturally and horticulturally.
If you need to know what some gentle types of fertilizers are, let us know. We're here to help (and toke).
