I have a 5-year old tree that has not borne fruit either this year or last. Two years ago we had almost two dozen lemons, however, with a bit less the first few summers before that. We live in northern Virginia and always move the tree outside in early March after the 20 degree temps are over. There are no tree suckers. The tree continues to grow new leaves and branches, and faces south with plenty of sun. I presume there are enough insects outside as well for pollination. Just can't figure out why no fruit.

thanks for any help.

Welcome to the Citrus Growers Forum. Thank you for joining, we are happy to have you as a member.

Three questions:

1) What temperature is the tree subjected to while setting in your residence throughout the winter months ?

(2) Does the tree bloom, but fails to set fruit ?

(3) How long has the tree been growing in the present medium. (When was the last time the tree was transplanted) ?

Lastly, even though you list your location in your thread, please go to your profile, and add to your profile the location of this tree. You can list state, city & state, or even the temperate zone number. Thank you for your cooperation.

Millet - (1,338-)

Milet's questions will help find the problem, but there are a couple more points--If you are getting lots of blooms but no fruit set, you probably are not pruning (you shouldn't in any case as that will reduce productivity --probably even prevent blooming for at least a yr).

Citrus trees do not need pollination (at least most do not), but they will only keep the amount of fruit it thinks it can support. That support is based on both nutrients and water. A tree that is poorly fed will not be able to support many fruit, but water stress is probably the biggest cause of fruit drop-especially in the period from bloom to June. If you tree is pot bound it may be going thru enough water stress to caus it to drop fruit.

Also Meyer lemons should bloom throughout the year and you should get a few fruit to set if you can keep the plant healthy through the summer months.

Okay, thank you very much Millet, Skeeter and Laaz for the quick feedback. I think this will answer your questions/comments.

From Skeeter:
You are right that I have not been pruning - I likely have not for the last two years.

From Millet:
1. House temperature in the winter is 65-70. The tree gets as much light as possible given our house layout.

2. Yes, hundreds of blossoms this spring but no fruit, not even tiny ones. Blossoms eventually drop off. Same thing last year. The year before we had a good 20 small lemons by now. Also got a fair amount of new leaves this spring.

3. I transplanted in mid-March this year. My planter is about as big as they come. I kind of peeled off the outer inch or two of root ball so I could get some new soil in the new planter.

Finally, I live in Reston, VA and updated my profile. I believe this is Zone 7 (DC is listed as 7-8 on Wikipedia). But I think I've read northern VA is zone 7 before.

thanks again,
Paul

You have covered most all of the required bases. Because the tree blooms, it must be acquiring enough stress house, and the tree must definitely be a mature tree. Had the tree experienced a dry soil period at any time during the blooming period, or does the tree set in the path of a heating or air conditioning vent? During bloom, the soil should never fall below 50 percent of container water capacity. Beyond these questions, unless there is some strange occurrence that we do not know about, I don't know of a reason that would cause the tree not to set fruit. However, to almost insure the possibility of fruit set, the next time the tree blooms, spray the flowers with a Gibberellic acid (GA3) spray. GA3 will artificially "pollinate" the flowers, and set the fruit on your tree. GA3 is how commercial mandarins, and other citrus varieties, are grown as seedless fruit. - Millet (1,334-)

where can you purchase GA3?

I purchased some GA3 from:
http://www.rarexoticseeds.com/Acid_Gibberellic_Powder_GA3_Poudre_Acide_Gibberellique_Smoke_Seed_Primer.html
It was my first purchase of GA3 & from this company. The service was excellent - delivered in a week without any problems.

I had gotten the GA3 info from Millet in a different forum:
link
and following his suggestions, used it on my Ponderosa lemon. I now have many fruit set - just hoping I don't now have fruit drop.

I would just mention that, I think, the concentration should be 10 parts per million (ppm) and not percent. Millet indicated this correct concentration in another forum:
link
and which is what I used with success.

Thank-you Millet for all your helpful posts - it has helped me alot in understanding citrus plants.

While GA will fool the tree into thinking the fruit has been pollinated, it will not cure an underlying problem such as water stress. Meyer Lemons are self pollinating (do not require cross pollinating), so if your tree is outdoor during the bloom period and you have bees, it is not likely that pollination is the problem causing your lack of fruit set. If your tree is not being pollinated by bees, GA will help.

Once citrus blooms have been pollinated, it is natural for most fruit to drop--less than 1 to 2% of flowers normally make it to fruit. A citrus tree will only keep as much fruit as it thinks it can support--it makes that decision based on nutrients and water supply.

If your tree is allowed to get too dry during the fruit set peroid, it will drop all fruit. If it is not fertilized properly, it will usually have low friut set. Container trees that are root bound can make it difficult to maintain the proper amount of water and nutrients.

Overwatering can also stress the tree and cause fruit drop (it basically kills roots and reduces both water and nutrient uptake).