I have a giant sunflower growing right now that is over 15 feet tall (I measured it from the roof last night). Some leaves are over 1 foot across and over 2 feet long! My question is, the seed head is just developing, and is about the size of a tea cup saucer and the plant has been in the soil growing since June. 1. What are my chances of developing a mature seed head this season? I mean, is it getting too late? 2. What are the chances of this sunflower self-pollinating so the seeds are viable (it is my only one). 3. Do I need to spray with copper when the rains come to prevent mildew?
hi. my garden is full of sunflowers, that self-seed themselves. however, i am in kelowna, and it is much drier. my guess is that your climate is warmer longer, so you should have loads of time for it to allow the seeds to mature. i have never heard of using copper for mildew. i have picked sunflowers before the seeds have fully matured ,and they have done so after being picked. as for cross-pollinating, there is always the possibility, so next season plant these seeds away from others that come up voluntarily. what color is your flower ? i am going to plant different colored sunflowers next year and start saving those seeds, ones that have dark smudges in the center. happy planting.
My sunflower two years ago was similar in height, but it made a huge head. I managed to get some mature seeds, and the next year's growth was not large at all. The offspring had no giant height characteristics.The squirrels removed many seeds and then the rains came. The rain caused some rot in the center of the head. So my limited experience indicates that sunflowers cannot withstand excessive wet. http://www.durgan.org/Blog/Durgan.html
Durang. . .did you grow your last years sunflower with, or between smaller varieties? I know that sunflowers can pollinate with other sunflowers very easily, and is it possible that this caused the seeds to produce poor offspring the next year round--if other varieties were smaller and contributed pollen? From what I understand it is hard or rare for sunflowers to self-pollinate, but I am hoping mine does, as there are none anywhere near here that I am aware of, and I would love to give the seeds another go. Cheers