How to Prune Overgrown Oleander
- 1). Prune your overgrown oleander in the early spring, before new growth is visible, each year for three consecutive years to safely renew the health of the shrub.
- 2). Cut back all plant tissue that is clearly dead, diseased, broken or otherwise damaged. Place cuts down into healthy wood just above a healthy leaf pair, lateral branch or bud. Clear away all of the dead cuttings so you can clearly see and access the remaining branches.
- 3). Remove one-third of the oldest branches all the way down to the crown, just above the soil line, in the first year of rejuvenation pruning. Make clean cuts with secateurs, loppers or a fine-toothed pruning saw. Distribute the cuts evenly throughout the shrub to keep a roughly symmetrical and natural appearance.
- 4). Sever one-half of the older branches that remain after the first year's culling. Remove these at the crown just above the soil. Distribute the cuts evenly to maintain an overall balanced form.
- 5). Prune away the last of the old wood in the third year, down to the crown. Shorten the terminal tips of any new growth that extends beyond the desired boundaries, if necessary, understanding that you will be decreasing bloom performance the more terminal growth you remove.
- 6). Carefully collect all of the cuttings during each and every pruning session both from the soil and from within the shrub canopy. Leaving cuttings to decay in the shrub invites disease and pests and also leaves the oleander looking unkempt.
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