I have 2 big Zucchini plants on my TG.  They have plenty of little prepubescent zucchinis with flower buds on them, but these female flowers will not open up so the very large and open male flowers can pollinate them.  Is this a common problem - perhaps more so with TGs?  I check online and it is common with conventional dirt gardens - some say the female flowers are "stressed" - but I couldn't find any real solutions.  Any suggestions?  Maybe buy them a drink or give them chocolates?