Mammoth Sunflowers

digitS'

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I think that's right.

I consider sunflowers an ornamental - too lazy to shell the seeds ;).

Therefore, they are fertilized with 16-16-16 - the same as all the ornamentals. I don't grow the mammoths but I'm a little surprised that you aren't seeing such frequent feeding of 3-2-1 as satisfactory. Expensive and bothersome, I would image.

Steve
 

Ridgerunner

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Is that 3-2-1 the numbers on the bag for concentration of Nitrogen, Phosphorus, and Potassium or is it some other ratio? Do you have a link to that product? If it is the N-P-K ratio it's higher than compost but not real high. You may need a fair amount of it. For example, the mushroom compost I saw at Lowe's was in the range of 0.5-0.5-0.2 for N-P-K. I can't remember if the P was 0.5 or 0.2.

I haven't grown sunflowers for several years, never did grow the mammoth. Goldfinches got the seeds before I did but that was OK, I was just growing for fun. I grew mine in with the corn, at the end of the rows.

Are you having issues or just asking in general? Unless your soil is really bad or something else is going on I'd expect you to be doing OK with a two week feeding of that. What stage are you in and how are they doing?
 

so lucky

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I don't recall ever even using fertilizer on my sunflowers, just chicken litter compost.
A few years ago some grew as volunteers in the chicken yard. They made good shade coverage and the chickens didn't bother the plants, remarkably. This year I planted some for the new chickens, put chicken wire up in a kind of lean-to so the chicks wouldn't be able to get to them. Not a good enough plan. They are voracious, and have eaten most of the seedlings. :(
 

flowerbug

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the chipmunks here find them when they are young and mow them down. the rest of the critters seem to like eating them too.

we don't grow the mammoth kinds any longer unless they show up from a bluejay stashing them around. we've not fertilized them ever, just plant them in rotation like any other crop. the black oil sunflowers are what show up mostly now. i tried some ornamentals but they never came back again.
 

seedcorn

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Here, the striped sunflower seeds go to waste. Black sunflower seeds never make it to winter. Once ripe, birds decimate.
 

ducks4you

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I planted sunflowers, cosmos and ornamental corn on the 8 inches between the south of the garage and the fencing I put up to support the first row of tomatoes. Also, planted some beans at the base. I see a few tiny seedlings up. About to leave for CO for a week. Should be interesting what I see when I come back. I have planted sunflowers and cosmos before and watched them droop. The fencing should help there. Don't care if the birds eat all of the seeds. I am trying to plant flowers with my vegetables this years and vegetables with my flowers to prevent weeds from taking up space. I will take picture of my potato bed this week to show the lettuce, spinach (gone to seed) and zinnias taking up almost all available space. VERY LITTLE weeding in this bed this year.
 

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