What is wrong with having purple on your tomato plants?

[Lavenderblue]

Lots have mine have got them. Should I worry about this? Or will they be OK in the end? I've always bought tomato plants and this is the first year I have grown from seed, so please excuse the ignorance. Mine are growing inside, I am just starting to put them out during the day to harden off.

[TEB]

I wonder if its phosphourous defiency which could be temporary as you are leaving them out during the day and they have got cold

[Lavenderblue]

Could be, they seem to be growing really well, have lovely healthy leaves and nice straight stems. I am going to pot them on soon so perhaps that will help a bit.

[shirlthegirl43]

Someone asked about that a few days ago and the reply was that they are a bit cold. I guess they are being hardened off a bit quickly?

[terrier]

Sun Tan! It takes them a while to get used to being outside.

[BarleySugar]

The phosphorus deficiency does turn them purple, with yellow between the veins. If that happens they just need to be warmed up a bit. They can't absorb phosporus from the soil if the temperature is too cold. My green tigers have recovered since the weather got a bit warmer at night, the new leaves look fine now.

[Lavenderblue]

hmm I have only just started to put them out during the day, just these past couple of days really while the weather has been so nice. At night they are in our bedroom for lack of any other room for them. This cottage can be very cold though, perhaps its that.

[teakdesk]

Yes they're most likely a bit cold and unable to take on the correct nutrients... unless they have used up all the nutrients in the compost!!

How big are they? What size pot are they in? What compost are they in?

You could give them a very, very weak liquid feed or pot them on to a larger pot if you are worried but they'll probably pull through Ok.

[Lavenderblue]

I think they need potting on. They are about 5" tall in various pots so they have probably used up all the nutrients. I will get them potted on tomorrow if the weather isn't to bad. thanks for the advice.