Last night's viewing - How to Grow a Planet, BBC2; Jo Brand on Kissing, BBC4

There's an obvious machismo problem if you're going to move from presenting a programme about tectonic forces to a series about botany. With the former you can abseil off the lip of an active volcano or do a piece to camera while diving into the flooded rift between two continental plates. It's positively Action Man compared to wandering through a wood and looking at flowers. So, kudos to Iain Stewart and the How to Grow a Planet production team for coming up with the most aggressively blokey way possible to convey the evolutionary advantage that toughened seeds confer on those plants that have them. Load up an empty shotgun cartridge with canna indica seeds and blast away at a plywood target. Excellent. You can do the slow-motion footage of the muzzle-flash. You can get your presenter to prod his finger through the smashed bull's-eye. And then you can plant the recovered "ammunition" and show how they can still do what seeds are meant to. If Guy Ritchie had been asked to film a GCSE biology module this is what it might have looked like. Except Vinnie Jones would have been wielding the shotgun, obviously.

The series is about how plants have changed the face of the world, and this week's episode concentrated on flowers, relatively late arrivals on the botanical scene. Stewart travelled to New Caledonia in the South Pacific to visit a primeval landscape of conifers and ferns, and to track down what botanists believe to have been one of the very earliest flowers – a tiny, pallid floret on an amberella tree that proved just a little bit more successful at attracting foraging insects than whatever had preceded it, and so spread. It's all about sex, really. Whereas the monkey puzzle tree doesn't reach sexual maturity until it's 40 years old, most flowers are at it almost immediately, giving them vastly increased odds of stumbling over some advantageous mutation, like the colours that advertise their seductive prospects to passing insects.

Stewart is occasionally a little casual in his language about this process. "The solution of flowers was inspired," he said about an evolutionary quirk that allowed one plant to ensure that its pollen would only be delivered to suitable recipients. It wasn't inspired, though, unless you believe in intelligent design, or fantasise that the flowers convened a brainstorming session to come up an answer. It was pure dumb luck leveraged by ecological advantage. Still, it was amazing, consisting of a pistil that only shot its wad in response to a particular frequency of wing-beat from a particular bee. Stewart got out a tuning fork and brought the flower to explosive climax in front of your eyes, a botanical money shot. Then he went off to explore a giant cave in Cambodia, just in case anybody was in doubt about his explorer credentials.

Jo Brand on Kissing was a classic example of Google-powered television – a loose miscellany of osculatory bits and pieces glued together with the kind of soundtrack you'd end up with if you did a search for "Songs with the word 'kiss' in the title". As far as I could see, the only reason for its existence was that yesterday was St Valentine's Day, though it's possible that this counted as an excuse, rather than a justification. Quick, someone may have thought, this is the one day of the year we might actually get away with broadcasting this. The only really interesting thing, still just discernible in the midst of a lot of hopelessly underpowered comedy "business", was the absolutely genuine reluctance of Brand to take part in a kissing workshop conducted by an acting coach. She'd started by saying she was averse to public kissing and she proved it here by flatly refusing to go lip to lip with her tutorial partner. Something of an anti-climactic climax, it has to be said, but at least you felt you were looking at something real.