Non-Blooming Climbers: Nitrogen vs. Phosphorus and Rootstock Takeover

Non-Blooming Climbers: Nitrogen vs. Phosphorus and Rootstock Takeover

Vigorous climbers may take 3 years to bloom—growth consumes energy. Reduce nitrogen (which fuels leaves) and use high-phosphorus fertilizer (middle number ~30, like Miracle-Gro bloom booster). If a climber has small red flowers, the grafted top may have died and the rootstock taken over—dig to check if canes originate below the graft union.