Oxford Planters supplies traditional and contemporary topiary specimens in box, yew and bay laurel. Their website features illustrations of the shapes available, along with an interesting history of topiary and maintenance tips. They also (as their name suggests) have a wide range of handmade wooden and lead planters.
David Harber has a range of sundials and garden water features which can be personalised. This would be a fitting tribute to your father and ultimately become a family heirloom. Another idea would be to have a garden bench inscribed. You might try Gaze Burvill, designers and builders of outdoor furniture in steam bent oak for a wonderful garden bench . Also try The Letter Exchange for ideas. This society can recommend professional letterers in all disciplines (stone carvers, sign writer, calligraphers) all over the country, and they might have some interesting ideas.
I do not believe obelisks are the solution here. Trellis might work for cover and for a framework for your roses or climbers. Anthony de Grey is a specialist in strongly constructed architectural trellis in Scandinavian redwood from sustainable sources. There are five ranges, with eight lattice options, available in over 100 different colours. The construction is modular, and panels from different ranges can be combined. You should also consider willow or hazel trellis available from Chairworks which could also successfully screen your garden.
You could try a company called Garden Affairs. They are specialists in stylish contemporary buildings including mini garden offices, summerhouses, log cabins, timber garages, arbours and garden stores. Their ‘posh shed’ division includes The Lynford Eco Store which combines a functional space for recycling boxes and an elegant garden feature.
Have you seen the range from deckchairstripes.com ? They offer traditional deckchair fabrics in 100% woven cotton in 45cm (18") wide widths and in a great selection of strong striped designs. One of their fabrics is also water-repellent (but softer than oilcloth).
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