Scent is undoubtedly the most instinctive of our senses, with the power to instantly transport us back to childhood and transform our mood with a mere fleeting whiff. Perhaps for this reason it is hard to measure and it is the least scientifically studied of the senses, especially when it comes to the scents of plants.

Despite fragrance being a multi-billion pound industry, the academic literature still contains surprisingly few studies investigating the profound effect botanical fragrance can have on our mental wellbeing. So while we wait for the science geeks to do their thing, here’s a list of five of the most-scented blooms which will allow you to enjoy the mystery of botanical scent all year round.

‘A richly sweet vanilla-meets-rose fragrance’: Daphne. Photograph: Robyn Mackenzie/Alamy

Coming into bloom when you need them most, the delicate pink flowers of Daphne start to open when winter days are at their darkest, filling the air with a richly sweet vanilla-meets-rose fragrance, like vintage perfume. What I love most about them is that you often smell them long before you see them, sending you on a hunt around the garden for the source of the incredible aroma. Produced on diminutive shrubs to fit in tiny spaces (they are even happy in pots), they provide fragrance to your plot from February to April.

I once went to a flower market in downtown Riga way back in the 1990s. A whole city street was filled with dozens of vendors selling the most incredible arrangements using only one species: the sweet pea. The scent of its ruffled pastel petals will forever be a flashback to that single summer’s day to me. Sown the previous autumn, plants will start producing their very first flowers from May, right through to at least July. To maximise the length of their season, gather the flowers regularly – as this triggers hormones which lead to the formation of new buds – and keep plants well fed and watered.

Probably the most floriferous scented plant there is, Trachelospermum will kick out a continuous display of white starry flowers from May to August, which can be so dense they almost smother their leaves. The intensity of their fragrance is similarly unbeatable and on hot summer days can be almost overpowering. An old-worldly fragrance that reminds me of fancy handcream, the plant’s dense leaves make them the perfect way to clothe a concrete wall in living green, or screen off an eyesore with fragrant wonder.

Buddleja flowers are a true magnet for bees providing them with a source of food from of September to October when most native flowers are long gone. Their abundance on waste ground and railway lines gives you an indication of just how easy they are to grow.

Finally, Mahonia x media will round up the year with sprays of sulphur-yellow flowers and a heady orange blossom-like aroma for months, taking you round to the first Daphne flowers in February.

Follow James on Twitter @Botanygeek