How To: Hydrangea Propagation

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.

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.

Enjoy!

P.S. Click Here for a downloadable PDF of this information.

How To: Rosemary Propagation

The rosemary is a vigorous shrub – its aromatic scent and lush green foliage is a favorite for everyone. The small blue flowers are always a delight. It prefers rocky, poor soil – I have a group of rosemary mothers tucked on a hot, rocky slope and they are doing better than the rosemary I planted in cultivated beds. Doesn’t need much fertilizer. Once established, the plant can take or leave watering. And my Sicilian Nana grew it in her backyard!

We just propagated 500 Rosmarinus Officinalis, your common rosemary, more to clean up the mothers than for production, but every little bit helps – and in this case, a little bit may be all we get. We usually propagate rosemary in the early fall or in the spring and summer. But, this winter we tried anyway. Unfortunately, our propagation environment failed us. Our hot table broke down; we had a cold snap and the soil media got a little too wet… so we lost several dozen starts – mold and stalk rot. More air circulation might have saved them – we will see; we have a fan on them now.

Propagation isn’t that hard, but you do need to get it right. Nothing wrong with being stubborn, but don’t be discouraged if your timing was off. And timing may have been the problem. During the late summer, I started several trays of Rosmarinus Officinalis in the shade house. They did quite well with a minimum of care. Bear in mind that different varietals may have different propagation requirements. Rosmarinus “Gorizia” may be more of a challenge than the “Officinalis”.

Let’s go over the rosemary propagation techniques and supplies you need for success.

•Propagation Supplies

- You will need a small pair of garden nippers, a sharp knife and razor blades. Any container will work, but six-packs are convenient.

- Acquire some rooting compound – I use KLN but Rootone is fine.

- Make your potting mix from half peat and half perlite – you want it lite and airy. You also want it moist, not wet.

- Your work space should be well lighted, but not in direct sun. Provide enough room for a small cutting board.

•How To

- Select disease-free stock. Take the fresh young growth (stem-tips) but take cuts that are only 2″ to 3″ long. Young plant material is best, it roots better. Keep these stem-tips cool.

- Take the stem-tips to your workbench. Fill the containers with your potting mix and moisten.

- Remove the lower needles from each stem-tip cut. Slice the lower end of the stem-tip with a diagonal cut – nice & clean

- Dip the stem-tip in the rooting hormone for a few moments.

- Stick each stem-tip into the potting mix.

•Rooting

- Provide a cool (65 70 F) and shady environment. Get a fan going for air circulation. Don’t let them dry out, but if they get too wet, they will rot (better not use a dome cover).

- In six to eight weeks, sometimes sooner, they will root. Give them plenty of time to fill their container before you pot up. Once rooted and going they like sun. They are a very attractive potted plant on the deck or patio.

Explore further
Herbs for Beginners
Rosemarys Outdoors and In
Floridata – Rosemarinus Officialis