"The seemingly spontaneous splitting that occurs in citrus fruits is discouraging. Splitting is an abiotic disorder, that is, it is a problem that cannot be attributed to any living organism, such as an insect or plant pathogen, but one that stems instead from environmental or cultural conditions. There is no chemical control for this physiological condition. The split usually starts at the stylar end of the fruit, which is the weakest point in the rind. Splits probably occur when water and sugar are transported from the roots of the tree to the ripening fruit, and the rind is unable to expand quickly enough to accommodate the added volume. The rind burst open under the pressure. Some citrus varieties, especially thin skinned ones, may be more likely to split than other varieties. Rinds that have been sunburned or otherwise damaged may be less elastic than normal and therefore more apt to split. Although the exact cause is unknown, fruit splitting is likely the result of stress to the tree. Splitting appears to be most closely related to extreme fluctuation in temperature, humidity, soil moisture, and possibly fertilizer levels, and the disorder is probably caused by a combination of these factors rather than by a single cause. For example, when hot weather is combined with high winds, the tree becomes drought stress and begins to take water from the fruit, causing the fruit to soften causing it to crack. Young trees or dwarf varieties with relatively small or shallow root systems, as well as trees grown in very sandy or porous soils that do not retain moisture well, may be more susceptible."

Kingwood, as Ryan has provided in a quotation (although Ryan, you forgot to cite your source), there are several reasons for citrus to crack. But, overall, the most common cause is due to irregular watering. What frequently can happen to more susceptible citrus (those with thinner, less elastic skins) is the tree suffers from a lack of water causing the fruit to shrink along with the skin, then gets a very large amount of water, which can cause the fruit to swell rapidly, and thus cracking the skin. This can be more pronounced if you're on sandy or DG soils. There are other causes or contributors, but in my experience, this is by far the most common cause. If you had a heat spell and didn't adjust your watering, then a cooling off period, especially if that cooler period is associated with a big rainfall, this may have caused the cracking. I have not had any cracking issues with my Cocktail trees, but then, we don't get the big rainfalls in the summer like other places do. And yes, the Cocktail grapefruit hybrid is an outstanding citrus, one of my top 5 favorites. It has all the delicious flavor of a grapefruit without the bitterness. And very juicy. Makes excellent juice as well as eating out of hand. Hope you can work out your watering practices and see if this is your cause. Let us know.

Patty S.

too much water when the fruits are ripening will cause splits.

this summer we've had sporadic rainfall. we had rain in early Mar, then a 3 month drought, then a lot of rain in late June and early July. then a few scattered showers in August.

getting our 1st cool front this weekend. =)

Thanks for the info. Was mainly trying to get info from someone growing it as to whether they had that problem also. Good to know it's only environment. I have had a splitting problem with my "Frankenstein Cara Cara" also the past few years. Prior to Cocktail, it was my sweetest citrus. It is very sweet. Since we have been having the drought conditions the past few years, it spits also. I know the mutated Cara Cara is splitting due to uneven watering. I have dug it up and put it in a pot to better control the water. Most of my trees are on flying dragon and I keep them managable. The cocktail and oroblanca came from a local propagator that I was not familar with and nothing on the tag to indicate rootstock.

By the way Patty, I purchased the cocktail and oroblanca based on your recommendation. You were right on with them. I prefer sweet/tart, but my wife prefers sweet. She will not normally taste a fruit that has split, but I talked her into tasting the cocktail and she ate the remaining split coctails and stated she can't wait to get some ripe ones. I also have two new kishsu. Waiting for them to grow up. Again, thanks for the info and referral.

Well, very glad you've got a happy wife! If she likes the Cocktail and the Cara Cara, you'll not get a single Kishu to yourself. It is out of this world good. And, if you can set a drip system on your citrus, so they get some regular watering, then just turn it off when you get heavy rains, you'll solve your splitting issues. Steady watering 2 or 3 times a week (depending on your heat), long enough to moisten the soil about 2 feet down will suffice.

Patty S.