Attached are the photos of my Cherry Tree. It is located at North York, Ontario. The flowers/blooms came alright. Then suddenly leaves started becoming yellow and now fully died. No fruits. How can I get fruits? Greatly appreciate your help.
There are a number of possible reasons why your cherry tree has yellowing leaves and is not producing any cherries this year. Some possible causes are: over watering, nutritional deficiency and disease or insects.
Over watering: in your photo it looks like you may be establishing a lawn around your tree? If this is the case stop watering the lawn near the tree. Remove any grass that is over the root area and replace it with 2 to 4 inches of mulch insuring it does not touch the trunk as this can cause it to rot. Water the tree every couple of weeks allowing it to dry out in between waterings.
Nutritional deficiency: an iron deficiency can cause leaves to yellow. Adding compost to the base of your tree and surrounding area may provide the nutrients it needs although ultimately a soil test can determine whether your tree is getting the right mix of nutrients.
Disease or insects: According to the US Cooperative Extension, bacterial spot of cherry is a fungal disease that causes extensive foliar damage. The disease favors heavy rain, wind and wet weather conditions for infection and spread. Symptoms of bacterial spot consist of water-soaked leaf spots with a brown to black color, leaf yellowing, numerous small holes on leaf surfaces and leaf drop. Infection can spread to the cherry fruit, causing dark brown spots and a sunken appearance. Cherry tree leaf spot is a disease of cherry foliage and fruit. The fungus favors wet, humid conditions for infection and temperatures between 60 to 68 degrees F. Small purple to brown leaf spots, leaf yellowing, leaf drop and small holes where leaf spots initially formed identify cherry leaf spot on foliage.
A couple of other thoughts: the cold spring we had this year could mean that while your cherry had blossoms, it did not set fruit. Also, you did not specify if your tree was a sweet or sour cherry. If it is sweet, it needs another cultivar of a sweet cherry for pollination.
Finally, here are links to a previous TMG question outlining good cultural practices for fruit trees (https://www.torontomastergardeners.ca/index.php/askagardener/no-fruit-on-my-apple-tree-in-my-back-yard/) and to an Ontario Ministry of Agriculture and Rural Affairs release on Fruit Trees in the Home Garden (https://www.omafra.gov.on.ca/english/crops/facts/fruit_home.htm)
I hope this is helpful in determining why your tree is struggling.