11

Sunflowers are tall, so contrary to most of the compositae (Asteraceae), the flowers appear vertically (and not horizontally). In this manner bees will see the flowers without the need to fly very high. But this means the flower is seen just in one direction. By moving towards the sun, the sunflower will be never in shadow, and it will be very visible to ...


9

Sunflowers that self-pollinate produce viable seeds. The only thing to watch out for is inbreeding, that is in a few generations the plants will exhibit traits that you don't see now on your current plant. If the seeds you planted come from already inbred plants, you will see the drift sooner, but if they were cross-pollinated with other plants from the same ...


7

It will help to find what variety you have, as some varieties need much wider spacing than others. Here is an idea of what you are looking for via spacing: 2-3' tall matured: Space 10-14" apart 3-4' tall matured: Space 12-18" apart 4-6' tall matured: Space 14-24" apart 6-8' tall matured: Space 16-30" apart 8-12' tall matured: Space 20-36" apart 12'-up: ...


7

If they're still there (not eaten, bored into, etc), then yes, they will grow. I have sunflowers naturalized along the woods' edge in one spot. They return year after year on their own. If you want to be organised, you won't be able to use seeds that fell on the ground (too hard to find), so you'll have to use what you can come up with out of the old heads. ...


6

Sunflowers and sunchokes are both members of the genus "helianthus", hence related and some similarities are to be expected - think family resemblance amongst cousins. Sunflowers' Latin name Helianthus annuus indicates that they are annuals, so if you have seedlings coming up, they will probably be sunflowers, not sunchokes. Sunchokes (Helianthus ...


6

Several possible problems come to mind. Firstly it could be a compatibility problem. Most sunflower varieties are, to some extent, self fertile. That is, they can produce viable seed even in a planting of only one variety. However, they will generally produce better if more than one variety is present. It could be a problem with pollination. Sunflowers are ...


6

According to this temperate climate permaculture site, they stay viable for 5 to 7 years. It lists the viability of a number of kinds of seeds, and I recognize the lengths stated for some seeds as being those I've seen listed elsewhere. However, this site says to consider sunflower seeds viable for the coming season only. It doesn't sound as if they know ...


5

I found a couple sunflowers that look like they could work. They are Dwarf Sunspot and Yellow Pygmy. They appear to have large heads and large seeds, and appear to be dwarfs. Dwarf Sunspot only gets 1–2 feet tall, has 10" heads on average (according to outsidepride.com), and has edible seeds. Yellow Pygmy gets about 2 feet tall with 8–10 inch blossoms. So, ...


4

You can do this, but the big asteracea leaves of the sunflower will shade the beans. Corn has been used for this purpose, and often also planted with squash or melons and that's called "three sisters". I have done it, it's a fun way to garden if you have an irregular space.


4

I think you were asking about propagating from the plant rather than the seed. I discovered this year that broken stems will develop roots if you put them in water. A slug had damaged the young stem badly, and, rather than consign it to the compost heap, I thought I'd see if I could save it. You can imagine how delighted I was when I saw roots starting to ...


4

A sunflower should produce seeds in the middle of the flower, so don't cut off all spent flowerheads. When they are ripe, the seeds can be easily removed or will fall off. The seeds may vary in colour, depending on the breed, but will most likely be in the grey-to-brown range, some may have stripes, some will be solid. If birds eat the seeds right from the ...


4

You can do it now. They look tall enough to thin but it won't hurt things to wait a week or so. It will depend on the variety as to the spacing. As J.Musser stated quite thoroughly, the height at maturity is a factor in the spacing. I avoid disturbing roots by taking my garden shears and snipping the seedlings off at ground level rather than pulling them....


4

You're unlikely to notice any big difference from this treatment. It would be more useful as a soil treatment. For consistent giant sunflowers, soil and light are the most important things to get right. That being said, foliar sprays aren't a bad idea, you just want to use something readily available for foliar uptake. It would be best to get a ...


4

I don't have so many squirrels, and I think they didn't know yet that such seeds are good. [and they could find easier way to get it: chicken foods contain a lot of sunflower seeds. BTW my sunflowers come originally from such chicken leftover] I see two possibilities: you could place a metallic net horizontally, and keep it. It should not disturb sunflowers....


4

Most likely sun scorch on the leaf tips, because they may not be used to all the sun light if you do not. As for the stem, it is a fungal dry rot. The soil is too wet and it looks like there is mold growing around it.


4

Based on this abstract Sunflower seeds are dormant at harvest time. They need a period of cold conditions to break this dormancy. It's a biological mechanism to prevent the plant from sprouting immediately and dying when winter comes before it can produce the next generation of seed. A few odd seeds may sprout, but they will be in the extreme minority. ...


4

Below is a photo of the single Sunflower ‘Sun King’ planted in our community garden patch this year. It has been entirely worth it! So many creatures have enjoyed this flower, including humans. It is no longer in flower and many birds are now picking out the seed or picking fallen seed off the mulch. In the same small bed we have successfully grown ...


4

The question of when to harvest the seeds depends a lot on how safe the seeds are in their current location. If not eaten by birds or varmints, the sunflower's seeds will remain viable outdoors until next spring at least. If you're confident the seeds are fairly safe from pests, it's best to wait until the plant is mostly dead before harvesting, to make ...


3

Sunflower plants are not frost tolerant, but the seedlings are, they will tolerate down to -3deg C at the cotyledon stage for a brief period; that is why the suggestion to sow 2 weeks before the last frost date is made, because it's unlikely the seedlings will be any size at all if there is a frost and will therefore survive. But once they become small or ...


3

So far as I'm aware, Tithonia varieties are no more sensitive to being transplanted than, say, Aquilegia or other plants that produce a tap root over time. You've got a choice; you either sow them in seed trays, then prick them out and grow them on in small pots, planting out when they're big enough and all risk of frost is past, or, you sow them direct, ...


3

Sunchokes will tend to attract smaller butterflies, especially (in my experience), the European cabbage butterfly (Pieris rapae). They might not be such an attraction to your monarch butterflies. Also see: Faunal Associations: The nectar and pollen of the flowers attract primarily bees, including bumblebees, cuckoo bees (Triepeolus spp.), digger bees (...


3

It is suggested that sunflowers be thinned when the first true leaves (the second set, which appears to be about now from your picture) to 1 plant every 2 feet, give or take. 2 feet is the suggested ideal spacing for bigger plants. If you don't care about size or specifically want them smaller you can keep a bit smaller spacing. As for the purple stems, ...


3

The cotyledon (the first leaf like green) will wilt and fade with time. That should be expected. That being said the other leaves are showing stress. There may more than one factor that is stressing it. One it's the wrong time of the year. If you are in the Northern Hemisphere it is early for sunflowers to start to grow. It may be the temperatures ...


3

Some varieties of Helianthus have multiple heads, like the variety Valentine for example. I don't know what variety you have there and where the seeds came from. They look more like a giant kind of variety (American giant?). Since they come from the same package (your one headed and your multiple headed plant), it could be that your multi head is a hybrid ...


2

I had mixed results with sun flower seeds this year. I work in over 6 gardens: 3 Boys and Girls Club, 2 elementary school, and my home gardens. Sun flowers need bees, butterflies, beetles or moths to pollinate. They do not have the self pollinating flowers like tomatoes & peppers. If you lack insects, buy or build a Mason Bee habitat. They do not make ...


2

I use foliar sprays extensively. I have found there are certain garden varieties which do not do well when sprayed with Epsom salt. Among these are Sage, and most succulents. I suspect the Sage fuzzy leaf surface plays a roll but all the other Mints I grow tolerate Epsom salt. Sunflower benefits mightily from my foliar sprays but I never use straight water/...


2

In general commercial seeds are viable for at least a year if kept dry, dark and cool (below 70 F). Dry is very important and you may want to use a metal container and toss in a desiccant package.


2

Lots of plants are grown under artificial lighting. Plants only need light to power photosynthesis so as long as you provide the correct wavelengths it doesn't really matter to them. Sunflowers are going to be a problem for you because of their height. You would be better off growing a dwarf species, and using a reflective grow tent as they do when they ...


2

Sunflowers have perfect flowers with both male and female parts. So, yes, it should be self-pollinating. Titan is an heirloom; so, it should breed true, too, provided it isn't cross-pollinated by another breed. There are said to be many flowers within each sunflower head. The first link I mentioned talks about how sunflowers protect themselves against ...


2

Probably the cause is lack of root room, since you're growing them in fairly shallow containers. Pot them up in good sized pots to allow space for good root development.


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