when growing in a south window it's important to remember the sun change's in the sky per season. IN the winter month's the sun is very low in the southern sky , when the sun go's through the glass it intensify's in heat , resulting in sun burn & heat stress. Each new growth should be larger than the last & it's super important to repot only when a new growth is makeing new roots . your orchid's would love to spend the summer out door's in your area from about mother's day to halloween. Out door's you can grow in less light & get more foot candle power. Good luck, keep at it, & remember " an orchid expert is some one who's killed a thousand orchid's ":
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