Possible Clues:

• Shrub providing flavour for gin
• At start of month traveller climbs tree
• Evergreen shrub or small tree with berry-like cones
• Plant, one pruned primarily within particular month, right?
• Shrub producing berries, strangely unripe after first of July
• Tree I planted primarily in month with "r" at the end
• Berry used to make gin
• Source of gin berries
• Shrub flavouring gin
• First of the month for each berry