The arboretum opens all year: daily 10am to 5pm from October to March with last admission 4pm, 10am to 6.30pm in April and September with last admission 5.30pm, and 10am to 8pm from May to August with last admission 7pm; no Christmas closure is printed. Guides are on site from 1 March, with free guided tours daily at noon and 3pm from March to October and buggy tours for visitors with disabilities by arrangement. The Slieve Coillte viewpoint across the L4027 is a standalone site with its own hours, 10am to 4pm from October to March, 10am to 5.30pm in April and September and 10am to 7pm from May to August, last admission an hour before closing and weather permitting because the hill is prone to coastal fog. Free admission for everyone on the first Wednesday of each month.
The visitor centre, cafe and paths near the centre are wheelchair accessible with accessible toilets at the centre and the cafe, but OPW lists challenging access and uneven walkways further out; a buggy and wheelchair-friendly orienteering course is one of four permanent courses. OPW lists both a cafe and a closed tearoom, so check the cafe is open; a playground stands beside it. Allow about an hour and a half.
Dogs: Pet dogs are welcome throughout the arboretum on a lead at all times, with a ticket at the kiosk; whether they may enter the visitor centre and cafe is not stated.
Photo: Two monkey puzzle trees on the lawn in front of the low, dark-roofed visitor centre of the John F. Kennedy Arboretum, with woodland behind. Mochorog, CC BY-SA 4.0. Source: https://commons.wikimedia.org/wiki/File:JFK_Arboretum.jpg. Licence: https://creativecommons.org/licenses/by-sa/4.0. Resized and cropped for display; derivatives retain the source licence.