Tomato leaves turned white

[cedillamuerta]

I started some tomatoes in early January in a greenhouse. Recently I took them home and uppotted them to 4" pots and kept them outside (because it's not winter here). One night it was going to freeze so I took them inside but didn't have time to bring them back out the next morning. A few days later (after only a day or so inside) their leaves started turning white. Did I blanch my tomatoes or was this something else? The new leaves that are growing now have no problems, but some of the leaves that were white are drying up and dying. Thanks for your assistance.

[hendi_alex]

Sounds like a combination of sun scald and/or wind burn. Tender plants can not go directly outside into the bright sunlight and wind. The bright light basically kills the chlorophyll and either parts or entire leaves will turn white or clear, with only the membrane left. Usually a plant will recover from this damage. When plants have been grown in soft light or indoors where there is minimal air circulation, they need to be gradually 'hardened' to the outside conditions. Start the plants out in semi shade or morning sun only for two or three hours plus place a barrier to block the wind from hitting the plant too directly. Over a period of one to two weeks, gradually give the plant more exposure to direct sunlight and more exposure to the full breeze.

[cedillamuerta]

Thanks, that makes sense. They haven't had much exposure to the wind since they've been kept in a sort-of alcove and it hasn't even been very windy. They have been on a western exposure, however, so that might be the problem. Crivens, I was worried they weren't getting enough light!