Orlah & Neta Revay

I have a blueberry bush that sends up new shoots which need their own 3 years. From my understanding they only give out good fruit on younger wood. Would it be allowed to keep old canes and graft new shoots that come out of the ground onto those old shoots and therefore from a halachic perspective it is old enough, but from a botanical perspective it is still young.

We just made aliyah and are renting an apartment from a non religious family that has lots of fruit trees. The trees are all more than 6 yrs old. I don't know and can't ascertain whether they observed any of the halachot of orlah. Since the trees are more than 4 yrs old, do I not have to be concerned or is there still something we need to do retroactively?

 Anything the trees produce this year we will be mafrish terumot and ma'aserot ourselves as they have given us permission to collect the fruits from the garden.

Recently I bought a blueberry seedling which, according to El-Rom Nursery, is considered two years old (halachically) and grown in a detached platform. The pot is perforated, and in my case it’s growing on tiles. Does it continue its orlah year count this way, or do I need to start counting again? And if at some point it’s placed directly on the ground, will I then need to restart the count?
Another question — the plant has both thicker and thinner branches growing from the main stem. Do I need to ensure that no new branches grow from the base, since that would mean starting the orlah count again for those branches? Or is the plant as a whole considered one entity, regardless of the branches?
Thank you.

Question: I saw that a green grocer's kashrut certificate in Jerusalem stated that only non-mehadrin stores are allowed to sell raspberries. Why is that?

A mashgiach of a large kashrut organization, who works in China, checked a company growing monk fruit in a greenhouse onsite. He found out that since monk plants produce the most fruit the first years, the company harvests the fruit only from monk plants during their first three years. In light of this, is monk fruit considered orlah? 

I want to grow a blueberry bush at home. You wrote that orlah applies to hydroponically grown trees. What about aeroponics?

 I want to grow a blueberry bush in my house hydroponically, using water and fertilizer. The bush produces fruit by its second year. Does orlah apply to trees grown hydroponically?

Are trees grown indoors, in unperforated pots, subject to orlah laws?

I heard that passionfruit is treated like a tree by Ashkenazim and thus obligated in orlah laws. So, my question is if we're allowed to eat passionfruit products (not the fruit - the products), like ice cream, juice, and the like when they are imported from outside Israel?

I planted a passionfruit vine as a living fence. Do I have to wait three years to eat the fruit?