Close up on a young white Nigra Mandshurica Hydrangea
Close up on a young white Nigra Mandshurica Hydrangea

Nigra Mandshurica Hydrangea to be specific. It’s a beautiful sturdy plant with a very distinct dark purple stalk, which is the reason we decided this was the hydrangea for us. Our propagation efforts have been a success, filling our hothouse with lush green foliage.

Every hydrangea has the ability to change color. Nigra Mandshuricas are naturally light pink, but hydrangeas will change from white to pink to purple to blue depending on the aluminum content of the soil. Aluminum changes the pH; acidic soil equals blue flowers, alkaline soil equals pink or purple flowers, and neutral soil equals a unique creamy white. If you add a penny or two to the soil around the base of a Nigra Mandshurica which is currently blooming pink it will change to blue; be warned its hard to change back again (but not impossible).

You’ll need:

•a few clean razors

•a sharp pair of nips

•a small to medium cutting board

•rooting compound (like Rootone)

•2 small containers (old yogurt cups work)

•6 six pack containers (makes one tray)

•a propagation tray with dome cover

•porous soil mixture

Optional* a 60-65° heating pad and a comfortable place to sit

I recommend preparing your cutting station first. Fill the six packs with the soil and water well. It’s better to water from underneath by dipping the six packs (into your sink perhaps). Place your cutting board with razors on a flat clean surface, with the rooting compound near by in one of the small containers. Place the well watered tray to one side.

Freshly poked Nigra Mandshurica Hydrangea cuttings.
Freshly poked Nigra Mandshurica Hydrangea cuttings.

You’ll want to propagate your hydrangea early on a spring morning when it’s cooler. Be sure the plant is well watered and select a young fresh non-flowering top. Make your first cut with the nips, keeping the stem-tip about 3-4” long. Place in one of the small containers full of cool water. If you’re unsure, take about 6-12 stem-tips then return to your cutting station. No matter how many you take, be sure they don’t wilt, if they wilt throw them away.

Back at your cutting station you want to keep the cuttings in water and out of direct sun. Remove the lower leaves if there are any. Take the two top leaves and pinch together, using your nips cut half to two-thirds of the leaf off. You do this to reduce transpiration (leaf sweat), lessen crowding in the tray and encourage root growth. You’ll then cut the base of the stem-tip at a 45° angle about 2” from where the leaves split off, dip gently into the rooting compound and place directly into the dirt, about 1” deep. Repeat.

You’ll want to keep the tray moist and well ventilated, if you use plastic covers take them off during the day. Keep the tray warm but don’t place in direct sunlight. If all goes well rooting should occur within 10-12 days. They can be potted up within 4-6 weeks. If they are destined for the outdoors, keep them inside at night for a few weeks and don’t but them in direct sun. Once they are big and strong, feel free to plant in the ground.


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