this might have been discussed on here before, but though i would just ask instead of trawling through years of posts.
anyone got any thoughts on which would prove better value for money between sunflower seeds and sunflower hearts?? there is a train of thought which suggests that although sunflower hearts cost more, you actually get more seeds per pound (£) than with sunflower seeds, making sunflower hearts better value for money (more seeds/£)
obviously the only way to actually test this is to count a set amount of seeds (100g) and see which you get more in, but it would save me a lot of time if others had an opinion on the matter.
A black sunflower seed is by weight between 35% and 45% husk (shell), let's take 40% for simplicity.
That means roughly 60% of the weight of the black sunflower seed is the 'heart'.
So if 10kg of black sunflower seed costs £15, you are getting 6kg of 'hearts' for £15. You can use this to compare prices between the black sunflower seeds and sunflower hearts on a 'heart' weight basis.
I find that they actually cost pretty much the same when you consider it in this way.
BUT starting from this rough cost-equivalance, one or the other can work out better value, depending on the situation.
For example: birds who eat seed with husks use an action to remove the husk before swallowing the seed. They do not recognise that sunflower hearts have no husks, and so they strip the outer part of the heart using the action that would normally strip the husk. So feeding sunflower hearts can actually waste part of the heart which drops to the ground, and therefore husked seeds would provide better value for money.
However, if the pieces of heart that are stripped and fall to the ground are then eaten by other birds, and this is what you intend, then the two types are more equivalent in terms of value for money.
In my experience, with lots of finches visiting a feeder the pieces of heart build up under the feeder and there aren't enough ground feeding birds to eat it all, or it gets damp and gets ignored, so for me seeds with husks represent the best value for money.
With black sunflower seeds almost 100% of the heart is eaten, but with sunflower hearts probably only 70% is eaten (feeding flocks of finches).
One final caveat: not all birds will eat seeds with husks (e.g. Goldfinch) so they are not strictly equivalent in feeding terms. I am going to try to feed the Goldfinches sunflower hearts and the other birds black sunflower this winter. To do this I am going to take advantage of the extra confidence of Goldfinches by placing the feeder with sunflower hearts much closer to the house than the other feeders.
I don't like to feed more sunflower hearts than I have to, on environmental grounds. This is because a machine (extra energy) has been used to remove the husks, and then a lot of the hearts can get wasted because the birds don't know they don't need to strip the husk.
The above is really written with finches in mind. I haven't spent any time observing any differences in behaviour of tits when eating hearts versus seeds with husks. But then finches generally massively outnumber tits at my feeders.