The idea you have in your head, is not possible. A single LED (like one tiny bulb, not a string) hanging on your evergreen shrub is going to consume about 1000x more energy than what could be expected to be available floating around the local airwaves. So - impossible.
But of course you could just increase the energy in the airwaves by 1000x, give the middle finger to the FCC, and risk having to take out a loan to cover your energy bill.
Or you could go for inductive coupling, which actually would be viable and has been demonstrated as "wireless energy" ad-nauseam for the last 120 years. You would just have to deal with extremely finicky LED alignment to get power from the very difficult to engineer and extremely power inefficient source coil which will bathe your front yard in a rapidly oscillating magnetic field. Again pissing off the FCC and super charging your energy usage.
Or you can just plug in your lights.
but
if you harness solar power during the day and use battery power at night, you could drive some, but not many, bulbs. More photovoltaics and parallel batteries would be needed to scale. But, it would be able to amplify the RF signal and effectively drive the bulbs by radio. I would recommend driving a near-field radio and not off of WiFi if you're going for any aesthetic effect. You could even drive it with the ambient audio (there are some integrated devices already like this, but wired).