orgoveg
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sunflowers - first timer - problems?

This is my first season experimenting with sunflowers. I'm interested in collecting the seeds to eat. I sowed seeds for a Mammoth Russian variety and all went well as they grew to about 9 feet in height. They began blooming about a week + 1/2 ago and produced flowerheads about 10" in diameter including the petals. Lots of honey bees have been observed visiting the tiny flowers in the heads.

All the while, I noticed carpenter ants all over them and they appeared to be most interested in dried brown "globs of funk" on the undersides of the leaves. I assumed these were eggs, but they looked more like fecal matter from some critter. The ants don't seem to be doing any damage and I considered that they might be beneficial as they may have been eating those "eggs". One of the main stems was covered with brown spots on its lower portion and it had a hole which oozed liquid when the stem was squeezed. The spots have slowly spread up the stem. The other plants have not been affected by this.

Two of the flowers began to droop a few days ago and they lost their outer petals. I covered the exposed roots with composted soil and watered more heavily. Now, all of them are drooping and the outer petals are either dried up or gone. I had the impression that these flowers tended to face the sun and would bloom for quite some time.

A little searching for information led me to believe that I may have over-watered them, but also hinted that all of this may be normal.

Advice? Observations?

Thanks.

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applestar
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I'm pretty sure your sunflowers are on schedule. The seed bearing flowers actually don't last long. Shortly after they flower, they lose their ability to follow the sun, and once the heads start to droop, they're just getting ready to mature the seeds. You may need to stake the stalks (or tie them to each other) at this point since they can become top-heavy and fall over.

At this point, if you want, you can cover the heads with some kind of insect screening material -- some people say tulle, I've also heard pieces of floating cover cut to size. Anything that dries fast. I've heard of paper bags being used too, but it wouldn't work in my area where it's humid with frequent thunder storms. To be honest, I never did this myself and just suffered the grub damage to % of the seeds. Covering the heads is also supposed to help against birds and animals.

When the back of the head turns yellow and the little individual flowers can be easily rubbed off the face of the seeds, the heads are ready to be cut off. I cut mine off because after this point, they are prone to black mold when left outside in the rain and humidity. I leave smaller flower heads with small seeds uncut for the birds.

I leave a fairly long stalk on -- at least 4~6" and remove all the outer petals and triangular bracts. I rub off all the individual flowers from the seeds and also remove any seeds with signs of grub infestation. The heads are tied with strings and hung inside as near to the ceiling as possible (from curtain rods in my case) -- but any warm and dry location will work. You want them to dry thoroughly.

Once they're dry, you can push the seeds off the heads. Sort out any with holes and put them in the bird feeder. I also sort out smaller seeds for use in the bird feeder later on. Be sure the seeds are COMPLETELY dry before storing them. Save the biggest seeds for planting next year.

** Oops, forgot about the ants: The ants are feeding off honeydew exuded by sucking insects. What you described as egglike mass are usually where Treehoppers are feeding on the vein. Treehoppers look like little brown thorns. They can chew enough to sever the main leaf vein, as you noticed. (I've not seen brown spot that spread? But may be some infection had set in from the damaged area. Brown rotten spots on leaves can also occur from being burned by bird poop on the leaves) I pick treehoppers off when I'm out in the garden, but not obsessively. The ants also feed off Lacebugs which seem to favor sunflowers. When I'm watering with the hose, I spray the ants and lacebugs off. Lacebugs cause tiny white dots on the leaves where they feed, that are also visible from the top. They're nearly invisible, so I just rub at the underside of any leaf area with tiny white dots. It works better with wet hands and even better with soapy wet hands. They weren't as much problem this year (at least so far), but Harlequin bugs also can be a problem on sunflowers.

orgoveg
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Wow. You know a thing or two about sunflowers, Applestar!

I have some tulle netting and I will follow all of your instructions.

Thanks alot!

OREOGARDEN
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I just started with my sunflower growing and my sunflower grew well till I found out when I got home from school I see that my leaves have fallen off my flower :( :( :( O:) I water them everyday I have more plants and the winter hasn't affected them so I'm worried that the winter weather is what may have killed them
Last edited by OREOGARDEN on Tue Dec 12, 2017 6:27 pm, edited 1 time in total.

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rainbowgardener
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Hi Oreo -- You said "leaves have fallen off my flower." Of course flowers do not have leaves. Did you mean the leaves have fallen off the plant or did you mean the petals have fallen off the flower? Those are two very different things with different causes. If you just meant the petals have fallen off the flower, read the earlier posts in this thread. That is a normal process.

imafan26
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have grown a few sunflowers. Mammoth has large edible seeds. Most of the multi-headed and smaller varieties don't have much meat to them. Sunflowers like to grow in full sun in well drained soil. They need regular but average water. Which means keep them from being totally dried out between watering.

They take about 7-14 days to sprout. Soaking seeds overnight speeds the process. It takes about 90-100 days for the sunflower to bloom. It takes alsmost a week for the flower to fully open, but it is only open for about 10 days. During that time bees and other beneficial insects will be stopping by to pollinate and collect nectar and pollen. Aphids, leaf hoppers will also be coming by. Ants can be beneficial but they also harbor and defend aphids, mealy bugs and other sucking pests so I put out terro ant bait at the base of the plant. You can also put tangle foot around the stem as a physical barrier.

No matter where you plant your sunflower, the head will almost always face the rising sun (usually east). The head will move to follow the sun until about noon when the sunflower will often be pointed almost directly upwards. Since the sunflower head can't really bend backward, it drops forward once it reaches its limit until the next day.

After ten days, the petals will start dropping off, the leaves will slowly start to dry. If the birds have a liking for sunflower seeds, you may have to cover the seed head to keep it from being robbed. The small brown flowers will dry and fall off, exposing the swelling seeds. It takes almost a month for the seed heads to totally dry. Then you can easily rub the seeds off.

It takes multiple visits for the flowers to be pollinated and since it is a composite flower, each individual flower in the seed head needs to be adequately pollinated. The seeds that did not get pollinated will be empty.



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