Purple leaves on seedlings is actually quite common - have several of them myself. ;) Sometimes it is just more noticeable.

In established plants it can be an indication of phosphorous and/or boron deficiency. But in seedlings it is usually just an indication of the stresses of growing and adapting to their growing conditions. As the plant matures and adapts the discoloring invariably disappears with no harm to the plant.

Sometimes it can be due to cooler temps - that is our current stressor in the greenhouse because most everything is getting a week of cool treatment in prep for hardening off. Sometimes it's soil that is too wet, sometimes the stresses associated with fertilization, etc. That stress causes the plant to have temporary difficulty absorbing and utilizing nutrients.

But attempts to correct it often cause additional problems so over the years we have learned to just leave them alone, monitor them, and give them some time. It passes. ;)

Dave

I agree with Dave, they'll change back to their normal color in no time.

EG

I should have said this, the plants have at least 3 sets of true leaves so I would not call them seedlings by any means..sorry about that..It does seem to be the ones that are closest to the back of the hoophouse so there would be less heat back there.. I have fertilized them 3 times I think, once each week for the last 3 weeks.. A couple of the purple leaves are starting to turn yellow now and actually are dieing.. I hope to get them planted next Monday, the weekend is to get below freezing again..

Yeah they are still seedlings. ;) They aren't established in their final growing place.

Yellowing of leaves usually means too much watering.

I hope to get them planted next Monday, the weekend is to get below freezing again.

Hmmm, sure seems awfully early for planting. I still have 2 weeks to go down here before its safe. When is your last frost date there? Ours is supposedly April 15th but the past 2 years we have had killer freezes as late as April 23 and 24.

Good luck.

Dave

Hi Dave, the last frost date is mid May, I guess now I am really confused.. first year gardner here, but I thought it was ok to plant broccoli out even when there will still be frost?? I am following these tables I got off the internet, the farmers almanac and the official seed starting site..

My fault! I was thinking tomatoes while typing, not broccoli. Duh! Call if a senior moment, ok? ;)

Yeah broccoli is ok as long as just light frosts and no hard freeze without protection. If they get hit with a really hard freeze they can "button up" and you don't get big heads. So if a hard freeze is predicted, cover them.

Apologies for the confusion.

Dave