Yes, they will sprout, and are easy to sprout. The difficulty is getting them to survive as small plants after they've sprouted. They need warmth, and the seedlings cannot be left outside during the Winter, even in zone 10.

Thanks Parker. I wasn't sure if this brand of fruit was a kind that got treated somehow before entering the United States. I can keep them warm as I have a greenhouse with Longan and Starfruit etc. that I overwinter in my zone 9a.

Keep in mind rambutan is considered an ultra-tropical and needs warmer temperatures than longan or starfruit.

Thanks I have Jackfruit and Cacao seedlings that Im going to have to keep warm. I used to keep my gh heater at the minimum I needed on night it froze but this year I'm going to be running it warmer. It still hasnt froze here this year but it probably will by Christmas. Feb is usually our coldest month.

I may just sprout the rambutans under lights and grow them indoors till March. They should be good outside until next November after that lol.

Cacao doesn't seem to like the heat too much, just prefers it mild but with high humidity. Take away the humidity and they go down hill fast, especially in warm weather. Rambutans also like higher humidity but they take to the heat far better than Cacao.

Thanks tropicbreeze, that is useful advice. I have my baby cacao trees in filtered sun shaded by a huge castor bean plant pretending to be the 'Madre De Cacao' lol. They gets lots of humidity here. We do have had some really hot summer temps like 100F a few times this year but generally 80's-90's in summer. We are still humid so it prob helped a little.

C Wes, your little Rambutans look nice and green. You must be doing something right :) I save a little rainwater when I can. I also have some in my tropical waterlily tubs that stay out year around. I will give them some of that.

A little OT... but does anyone think I should separate my Jackfruit tree seedlings before they go in my greenhouse? They are 5 per 1 gallon pot (I know, bad right lol). I have 3 pots of them. Some are close to 2ft tall so they are really crowded. I was gonna wait till spring but if they are going to grow all winter they could be pretty big by then. Will they continue to grow a lot during winter or do they typically slow down?

I lost two Cacao and gave up. Our dry season (winter) is too hot and dry. Got a few years and good growth during the wet seasons but the dry seasons were a killer until they finally succumbed.

Haven't tried Rambutan yet but it's grown commercially here. Mainly exported to Japan, they get good prices for quality fruit, more than they get locally. Usually Mangos are planted around the Rambutan orchards to protect them from dry winds.

The least root disturbance you have the better it is for Jakfruit. I plant one seed per pot. In my opinion you're better off to separate the seedlings (or saplings now?) before they get too big with intertwined roots.

I have read in a book that rambutan suffers plant damage with temperatures below 45 degrees. Since I do not have a greenhouse I didn't even try to grow them. If anyone finds out they can take temperatures lower than that I would like to know.

Some tropical plants can weather a short, sharp down spike in temperature provided it warms up quickly afterwards to a reasonably level. But that's 'reasonable' by tropical standards, not by cold climate standards. The length of time they're subjected to low temperatures is the most important factor, not necessarily the actual lowest temperature.

I've sprouted some but you would want fresh fruit/seeds. When fruits are bright red. Zone 9 you have a decent chance after a couple years to keep it in a big pot or something.