Answer: You need a tolerant plant for this position. This is a harsh environment for any plant because the light coming in is uneven, unlike in a greenhouse or conservatory. Porches tend not to be big on ventilation, so this presents its own problems with the lack of ability to control widely fluctuating temperatures.
Just like conservatories and greenhouses, shading from summer sunshine is recommended. This will increase the range of plants that can be grown. As long as the temperature in winter does not drop below 5°C in winter, the most tolerant plants will include pelargoniums, cacti and succulents, Nerium oleander, citrus plants and the bird of paradise plant - Strelitzia reginae.
With the shading, the Canary Island date palm – Phoenix canariensis - should also work well in the porch.
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