Nepenthes rajah is comparable to that experienced in nature, since Borneo lies on the equator. Pure long-fibre "Sphagnum" moss is an excellent potting medium, though combinations involving any of the following – peat, perlite, vermiculite, sand, lava rock, pumice, "Osmunda" fibre, orchid bark and horticultural charcoal – may be used with equal success. The potting medium should be well-drained and not too compacted. Moss is useful for moisture retention near the roots. The mix should be thoroughly soaked in water prior to potting the plant. It has been noted that "N. rajah" produces a very extensive root system (for a "Nepenthes") and,
Blawhorn Moss National Nature Reserve area by the International Union for Conservation of Nature, and is also designated as both a Special Area of Conservation and a Site of Special Scientific Interest. The reserve is owned and managed by Scottish Natural Heritage (SNH). Blawhorn Moss provides an important habitat for wildlife and supports many of the plant species representative of bog habitat. A number of sphagnum mosses grow here, as well as heather, crowberry, hare’s-tail cotton grass and common cotton grass. A variety of bird species breed on the moss, including red grouse, snipe, curlew and redshank. Stonechat, skylark and meadow pipit are also regularly