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https://en.wikipedia.org/wiki/Photosynthetic_efficiency:

  Quoted values sunlight-to-biomass efficiency

  Plants, typical     0.1% [3], 0.2–2% [4], 3.5-4.3% [5]
  Typical crop plants 1–2% [3]

Solar cells can turn about 10% of incoming sunlight into electricity (cells are more efficient, but they don’t cover the whole ground, typically aren’t kept optimally oriented, etc)

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Solar cells are more efficient and last longer, but don't grow themselves from seeds produced by the previous generation. That makes it much more expensive to cover large areas with them.

Plants are much easier to recycle as well.

Biodegradable by definition.

The maintenance is much more expensive and time consuming though. Most solar panels are install and forget for their lifetime measured in decades, with some small failure rate in the meantime. Plants however typically require maintenance multiple times a year and most have usable lifetime measured in months, not decades.

There are more types of plants than just corn. Trees are much easier and cheaper to establish than solar for example.

Trees are the lowest of that low range that start at 0.1% efficiency.

And if you collect only the wood, it's a couple of magnitude lower than it.

But delivering the energy from those trees to consumers is harder and more expensive than for solar cells.

Also, if your desired output is electrical power, you’ll lose more energy converting your trees to electricity.

On the plus side for trees, storing the energy they stored is cheap, and can be done for centuries.

The net effect is that PV cells are more economically viable than using photosynthesis to catch solar energy (at least for now; there’s work being done on improving photosynthesis; I don’t see that beating PV soon, though, certainly not because PV cells keep improving fairly rapidly)

Trees are often turned into heat and energy. Obviously they have very different requirements from PV cells and overall probably aren't as good they are certainly viable in some places (e.g Italy).

Somehow it just doesn’t feel right to burn trees to produce clean or green energy. It might work on a small scale but not sure about doing it on an industrial scale.

It might be renewable but it still makes air pollution. On certain nights when everyone in the neighborhood decides to have a fire the air quality is terrible - almost as bad as during summer forest fire season.

and plants are not only energy storage. They are great water storage, air cleaners, area temperature regulators. Not even counting as habitat for rich fauna fungi...life.

Still waiting to hear a politician running on the platform of more plants.

Plants are enormous consumers of water. The water argument is strongly in favor of PV.

There is a lot more to water than consumption. Overall trees usually have a positive effect on water flows.

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