Watering outdoor

If your outdoor soil is fairly loose, I would use the the two knuckle approach as in indoor growing. If the soil does not stick to your finger, nor feels damp(kinda sandy/powdery), then water the plant. The larger the plant, the more you need to water (slowly) the soil, to get to those deeper roots. During the summer, you may hit a point where the plant just starts to droop, that is also a good indicator of how long to wait, from your last watering. Those durations will vary as temp, wind and precipitation will shorten or lengthen the dry period. You'll figure it out, as you go. Good growing!