I couldn't resist any longer. For years I have tried, but defences got weaker and weaker and now I've given in to temptation and at the moment of writing I am in a state of delirious jubilation for it. At long last I have treated myself to a Trachelospermum jasminoides. It is also called false jasmine or star jasmine on account of its similar looking clusters of small white flowers and the equally strong fragrance. But to my nose the Trachelospermum is far superior: not sickeningly sweet and overpowering, just strong, exotic and refined.

Neighbours at the back of our block have a huge plant climbing the fence to a van company next door and in summer, whenever I leave the building, there is this scented cloud drifting towards my nostrils. Whenever I get a whiff of it, I lose every restrain and start sniffing like a dog on a fox's trail - whether I'm in "polite conversation" (at which I am useless anyway, I'm afraid) or else. It took all my will power just to stop myself from running out for no better reason than to smell it again. So why then didn't I buy my own plant any earlier? Lack of space, of course.

There were three Clematis montana var. rubens and a Parthenocissus quinquefolia covering every square inch of the fences until recently. Madness to have four such strong climbers in such small plot! But we were tenants and only looking after them. Meaning de facto I'd constantly have to prune them. Eventually, with some intervention from fate in the form of our next-door neighbours, the clematis plants one by one went.

The Parthenocissus has happily sized its chance since and romps unhampered by competitors over everything on one side of the garden. On the opposite side I now have trained half my rose to the fence. Then there was the decision of what plant to grow up the third panel: sunny for half a day and in summer only. I badly wanted a Trachelospermum. But would it be happy in this spot? My book says it needs sun. At least, in order to flower really well. Yet it is evergreen, with shiny, somewhat leathery, dark green oval leaves: It would look good and hide the ugly fence even if it didn't flower as well as I hoped.

But what if it actually was happy there? Would it turn into just such a monster as the Clematis montana had been, suffocating and strangling each and everything within reach? The book spoke of twining shoots, several metres long, vigorous growth, up to 9 metres tall! In other words: Wouldn't I send myself from the frying-pan into the fire? Don't do it, said my head. Do go for it, said desire.

In the end, it was pity and loyalty that made me decide in favour of Passiflora caerulea. Certainly not a very good choice for my plot. The London clay in the bed had been improved with leaf mould and years of dumping spent multipurpose compost from pots there, so I don't worry too much on that front. Yet Passiflora caerulea too needs much sun and is a vigorous climber. Unlike Trachelospermum though, it is not evergreen but on the contrary late to emerge and get into leaf - not before May or even June here - and, left untended, has an untidy growth at that, much like the true jasmine. Not what you'd want if you intend to hide something all year round.

But this plant was one of those I had promised "release" for years. In fact, it had come with me from Germany nine yeas ago where originally I had bought it as a houseplant. They are sold as houseplants there, the shoots tied round and round a wire wreath, condemned like a hamster in a wheel. All its life it had spent in a pot and for the past few years had tried its best to withstand the onslaught of the Parthenocissus mauling it in its corner. An unfair battle, as the Passiflora's resources were so limited. I loved its spectacular flowers and the occasional bright orange fruit in autumn and wanted to see it reach its potential. So in it went in the prized - since rare - spot of ground last October. I'm sorry to say I'm still waiting for it to show potential - but freedom can be hard to suffer, I guess. So give it time...

Back to the Trachelospermum though. No, space in my garden obviously didn't increase. But this summer the fragrant clouds proved just too tempting. Moreover, I had come to the conclusion that a) this climber didn't need full sun to flower after all - proved by some specimens that had teased my nose in the semi-shade of a pub garden - and b) I found you could tame the monster. In a front garden in Kew I had seen a panel of green and white up the house wall that on closer inspection turned out to be Trachelospermum: regularly tied to a trellis and rigorously clipped, like a vertical formal hedge.

It looked very neat with its smallish leaves and still flowered profusely. Checking the "RHS Encyclopedia of Garden Plants", I find it belongs to the same "Pruning Group 11" as does Clematis montana. Both need no regular pruning but can be trimmed "to fit available space", it says. There is a difference though. Apart from the Clematis being deciduous, i.e. losing its leaves in winter, and being much broader leaved (making it look less neat and tidy, even when cut), you would forfeit next year's flowers if you prune the it later in the year when it really gets going and strangles everything. The reason for this is that Clematis montana blooms on last year's growth. Trachelospermum on the other hand flowers on current year's growth - so while pruning in late winter or early spring is recommended, you can snip bits off pretty much any time and just lose part of the flowers or delay them, I would say.

So if for some reason the Passiflora in my garden proves ungrateful or overwhelmed by its new found freedom, I can entertain the hope of training that evergreen monster Trachelospermum into a dense green veneer for the fence. But where do I put it if this "opportunity" does not become available? At the moment, I frankly don't care: Columbia Road Market sold strong plants, a metre high and bedecked with flowers, for £ 10. Every time I enter the garden now I'm enveloped by its intoxicating fragrance and feel like a child with an ice lolly.

I felt quite silly and I'm sure if the guard wasn't so polite he would have grinned. That happens when you are tempted by colourful and quirky posters seen from the tube but are too lazy to find out more about an exhibition before you go. Plantastic! these posters had screamed, and since anything with the word "plant" in it stirs my curiosity, I had gone to the Horniman Museum in South London the other day.

If I had been familiar with the Horniman, I would have known: they do a great line in educating children and families. But here I was, on my own, entering a room that was clearly designed to entertain and teach children of roughly nursery and primary school age: huge colourful, toy-like wooden flowers, apples, bees etc. - plenty of them with screens set in. Well, what to do? In the name of research - and since I had made the journey and paid the ticket anyway - I went round and tried every single thing on offer.

Once the initial disappointment was over and I had adapted to the situation, I must admit I found it quite fun. If you have children of the above mentioned age-group and are in London, go see. They will love it: it is all interactive, so no (or very few) exhibits in glass cases but lots of things to do. I'm sure mine aren't the only ones who, given half a chance, will hammer their fingers on any screen or press any button in sight.

So what is there to do? The really small ones can crawl through a tunnel that represents a root system and see if they can find a stuffed mole and rabbits along the way. They may also enjoy the time lapse video showing the decomposing of dead plant matter with fungi growing out of it eventually. Also for the smallest visitors perhaps is the installation of wooden sunflowers which "follow" the "sun" like their real-life counterparts if you turn the rail left or right. Or the human-like figure you can feed cards with plant pictures printed onto them: if it's an edible one, a green light will show and the figure will grunt approvingly. If poisonous, you see the red light - accompanied by a sound that will delight children but is
unfit for the dinner table...

There are puzzles to assemble - both traditional and 3D. There are plants to be matched with their pollinators and scents you can sniff with the flower that emits them. There is brass rubbing of prehistoric plant forms, and picture cubes to be arranged in the correct order of a food chain. You can draw your own fantasy flower and see it appear on a big screen. Likewise, you can choose from a number of plants and drag them on screen to create a wildlife-friendly garden. At the end, the wildlife these plants might support appears on screen, too, along with some predators - butterflies, bumblebees, snails, a hedgehog here, a fox there.

I was quite glad no one was around when I tried the game that's like those classic car races, only in this case you are a joystick-manoeuvred bee buzzing through blades of grass, aiming to find flowers as fast as possible. I can't remember whether I ever played a game with a joystick before - and I'm certainly no natural. I regularly banged my poor bee full speed against the blades, resulting in probably a nasty headache as it seemed not only to bounce backwards but loose orientation for a number of seconds...

A little more educational, there are real-life seeds, grouped according to how they are dispersed in nature: by wind, water, fire, hanging on to animals or being buried by them as food store. There is a huge touchscreen "book" that tells about the ancestors of wheat, potatoes and the tulip and a quiz on plant facts. For children (of course!), I also liked the "powerplant" installation where, if you choose correctly what a plant needs for photosynthesis, an apparatus lights up green and starts bubbling.

Regarding contemporary topics, there is the game that teaches (on a basic level) how you will increase or reduce your carbon footprint - lots of blinking lights that need pressing at the correct moment in a race against time. And they also cover four "thorny issues" as they were called - pollution, climate change, rainforest destruction and GM crops. Interestingly, the last one did not really respond to touch anymore: Did militant opponents (or supporters?) hammer too furiously on the screen and broke it I wonder?

Coproduced by institutions from the Netherlands, France, the UK and Belgium, Plantastic! is at the Horniman Museum until November 1st. If your children are interested in plants or you want to get them interested, there are worse ways to go about than visiting this exhibition. I'm sure I'll drag mine there during the school holidays this summer - but might leave the bee race to them: you'd want to avoid embarrassing yourself in front of them if you can, no?