One question. How difficult do you guys think it would be to use pollen from my emperor to pollinate the blooms on my sweetheart. I know it will take many years, but my goal is to produce seedlings and eventual fruit that are emperor x sweetheart. I am hoping the cross would offer some of the flavor from the sweetheart, and hopefully hold the growth habit of the emperor. I guess I would have to bag some female blooms on the sweetheart?

Hey jsvand5, you are so lucky you have blooms already. How big are your Lychee plants? If you want to just use polled from your Emperor to polinate your Sweetheart, it shouldn't be too difficult but you would definitely need to bag some flowers. It may be wise to bag individual flowers and not the entire bloom spike because the bloom spike can be a combination of male, female, and mixed flowers. You may also need to store pollen because your different lychee varieties may not bloom at the same time. When doing crosses with plants that don't grow true to seed or plants that have a large and varied gene pools, it can be very difficult to get the traits you want. You may grow 100 plants to full maturity and still not get the traits you want. It may be easier to plant the Emperor lychee seeds and graft Sweetheart on top of it. I've read it used to be difficult to graft lychees but more and more people are having success with it. When you graft, it may stunt the growth of your lychee and give it a more compact form like the Emperor. Have any of your lychees fruited before? Man, I can't wait untill my plants finally fruit. At least I can head to the local nursery and taste test all the varieties they have:)

I am thinking the best way to go for the cross pollination may be to try to remove all of the male blooms from one stalk, pollinate the females with the emperor pollen, and then bag the stalk. I may end up having to reverse it and use the sweetheart as the pollinator because the emperor flowers are not ready to open yet. Do you know how long stored pollen can stay viable?

This is my first year with them so no fruit before this. I have 3 in pots and one in ground. They are all around 4 ft, but the emperor is a bit larger. I am going to let the container ones hold most of the fruit assuming they set some. I want to keep those small anyway so I'm not too worried about stunting them. I'll probably let the sweetheart only hold a smaller amount of fruit. That one will have it's own greenhouse by next winter so I want to let it put on some good size.

I agree with what Simon had to say about the cross pollination. You never know what you'll get, and that experiment could take a very long time. There is no feasible way to bag individual flowers though, they'll just pop right off from the weight, so cutting the males off, pollinating, then bagging would be an optimal solution.
I believe pollen is viable for up to 3 months...maybe longer if frozen.

NTM...have you tried collecting the pollen, putting it into a solution, then spraying the females? If so, what solution? Just water?

I know it will take years and years to find out if I even got a cross that produces good fruit, but I figure since I know I would plant a few seeds from this years crop anyway, I might as well go for something a little different. I am hoping the Emperor blooms overlap the sweetheart blooms at least a little. I was thinking by using emperor pollen on the sweetheart I could possibly tell if I at least had a succesful cross if some of the resulting seedlings leaves take on some of the emperors leaf type.

@Jay- I haven't tried this technique, but it is possible. I'd probably recommend distilled water to make the solution. The sweetheart pollen is kind of sparse, so trying this with an Emperor would be a lot easier. The emperor seems to yield mostly males, while the sweetheart yields mostly females.

Well so far all I have are female flowers opening on my Hak ip. I have searched the blooms many times and not a single male among them. Most of the flowers have not opened yet but I am getting a little worried. Anyone know how many days the flowers opened before it's too late for them to be fertilized? There are tons of bees all over them. Now I just need a little pollen for them to spread.

Hey jsvand5, the small group of lychee growers on this forum should consider swapping pollen. You live in Florida right? Isn't Pine Island Nursery or Lycheesonline in Florida? Perhaps you can visit a lychee grower and collect some pollen to pollinate your female flowers. It would totally be worth the trip. Man, I'm so envious of you guys that have lychee trees in bloom already.

Js, I wonder if that's what happened to my Sweetheart blooms last year? I didn't know the difference between
male and female flowers(still not sure) so I didn't know what to look for. Maybe all I had was female flowers and they never got fertilized, could be why I never had a single one form into fruit? Just a guess...

According to them, "the male flowers typically open before females on lychees"

Below is a link to a close-up pic of set Lychee Female Bloom...click on it to really enlarge it...

Here is a link that might be useful: Closeup of set female bloom... from Lycheesonline

@Puglvr- The M1 males open first, then the females, then the M2 males. That is the order of flower emergence. Some cultivars don't have M1 flowers though (i.e. sweetheart), so the females open first, then the M2 males open up. A perfect example of a female is in Jsvand's last pic in this thread...females have that curly "Y" shape pistil above the ovaries...very distinct.

That pic is from my Hak ip. Do you know if the Hak ip has male F1 flowers NTM? What do the male F2 flowers look like?

Thanks NTM :o)

Appreciate the clear explanation...helps me a lot! Not to say I still won't have questions, though,LOL...this flower thing is still a little too complicated for me. Last year, I tried hand pollinating my Pineapple Guava, NO luck. I'm sure its because I had no idea exactly what I was doing?

Oh well, I guess I will have to leave to mother nature, the bees and other bugs...

@Jsvand- The males look roughly the same. The M1's are more flattened in the center of the flower, and the M2's seem more hermaphroditic. The pollen characteristics are different too, but that is all. If all that you see emerge first are females, then you'll get M2's for pollen.

@puglvr- I'm glad to help out. Letting the bees do the job isn't a bad idea at all either...they're the experts ;)