If your temperature and light levels are OK then you should be able to solve the problem by your choice of rootstock or by building a shelter over your plant. There are growers worldwide growing all sorts of crops in high tunnels covered with clear poly. You might need to divert the water away from the roots.

This might not work but is worth a thought.

The Fruitnut

I agree that what rootstock you chose is going to have a lot to do with your success or failure. I don't know enough about citrus rootstocks to help you chose either.

However if I were going to try to grow in that kind of environment here is what I would do.

I would plant the tree on a mound or row if planting more than one tree. The mound or row would need to be a minimum of three feet above the estimated high water mark. Place plastic sheets or tarps over the mound or row to so that the water will run off.

If the tree needs to be watered you can pull back the plastic sheet or tarp and give it some water. Or I might install some of those watering tapes around the tree before I put the tarps down. I might even be put it on a timer.

I'm so glad it does not rain here very often.

Try poncirus rootstock. It tolerates cold and wet soil.

Hi
We could make all kinds of suggestions but what choices are available to you?? I'd check around locally to see what others are doing and what they use??
Where does the market supply of Grapefruit come from in your area?? Obviously they overcame all the problems??
If they have fruit they're using the right kind for sure!! Good luck gary

Thanks, everyone, for your suggestions.

First, there is no local supply here. I don't think there's any in India, either. We have some great and interesting citrus but no grapefruit.

I was assuming I'd bring seeds/cuttings/root stock in from the US. Nepal is not at all strict about importing plants.

We have absolutely not fancy gear here, so no watering tapes (I don't even know what one is!). But I get the idea
about covering the plant.

I've been pondering the idea of introducing grapefruit as a cash crop for farmers here. About 85% of the population are subsistence farmers and they really need salable crops. Seems like it might be a good fit.

I'll look into poncirus. Thanks for the suggestion.
My first question on GardenWeb forums. What a great place!

I am originally from India. I am aware that there are other South East Asian countries and Australia/NZ etc that grow the grapefruit commercially. You might want to check with some of those growers about the rootstock and pest resistance of varieties for Asian climates. There are several esteemed agricultural universities in India too that might be able to give you more information on the best variety of grapefruit suitable for you and its care and maintenance. I would also suggest that you get in touch with the University of California Riverside's citrus research station for help. They are world leaders in citrus research.
Personally, I like the Oro Blanco grapefruit and it can take quite a bit of cold temperatutes compared to others. If it is grafted onto a Flying Dragon rootstock, it might help with your low temperatures. Also, this variety is quite a valuable, sought after and expensive crop even in the US. There are only a few farmers in california who have started growing it in small acerages and the fruit goes for around $2 a piece in the local specialty markets. You might even hit the export market if you succeed. Good luck and keep us posted.

Thanks, AshleySF. I'll try to get to all that when I can. Great suggestions, but it might be too heavy for export. We'll see.

Wow, thanks for the information, Ashley!
Mike's recommended the Oro Blanco, and it is readily available at the local nurseries....but I didn't realize it's specialty value.

Josh

Josh, I am not a fan of the "bitter" taste of grapefruit. I talked to a local "expert" at Yamagami's nursery (SJ area) and they recommended Oro Blanco because it tastes very sweet, easy to peel, seedless and because it is best adapted to the Bay Area climate where temperature could hit 20s in the winter. I see that you are in NorCal, so it is a good choice for you :)

Oro Blanco rocks!!!!!!!!

I have one, as Josh says, and is it resilient!!

I would also too while making a mound for your tree, I would also manipulate the soil so it drains very feely!

I am sure there must be many ideas people have that they can give you, so you could amend the soil to make it so it doesn't hold much water..I am just brain dead right now, but I wanted to wish you much success...

Mike

if the local citrus is pummelo, then you should not have a problem with freezing, since grapefruit will take as much as a pummelo or even colder.
The root stock that is used locally for the pummelo might be a good choice for grapefruit. If you can find out what they are using for root stock locally, someone here could tell you if grapefruit will graft well to it.
Oro Blanco is a cross of pummelo and grapefruit. if you are wanting the tart of grapefruit, I would recomend a full blooded grapefruit like Rube, Indian Red or Marsh. The varieties that do best in Texas would be your best choice, since Texas is more humid so closer to your climate.
Your biggest challenge with grapefruit is getting enough hot weather to make them sweet. (sweet by grapefruit standards that is) Grapefruit love the hottest citrus growing areas and still take at least 10 months to ripen and are best after 14 months