Growing Anemones and Ranunculus

Growing Anemones and Ranunculus

Anemones and ranunculus are some of the most popular flowers we grow! They bloom roughly from March through May and provide a spectacular start to spring.

These flowers take years of trial and error to grow well, although even less-than-professional results are lovely. If you are interested in growing anemones and ranunculus in your garden, there are a few helpful things to know. These principles are true for growing anything, but they apply particularly when your goals are more advanced:

  1. You are the expert on your own property. You know more about your own yard than anybody else -- where the water pools (bad for most plants), where the sun hits for more than 6 hours (good for most plants), etc. You should feel confident in your observations! The flip side of this coin is that no one can tell you exactly what to do because your situation and microclimate are unique. Expect to figure out lots of things for yourself.
  2. Nobody gets everything right the first time. Growing plants is so rewarding because isn't easy. Be gentle with yourself and understand that you might not grow anemones and ranunculus perfectly the first year.
  3. Don't skimp on the soil. Plant health begins in the soil. If you think it's a good idea to dig a hole in a patch of grass and throw some ranunculus corms in, you are wasting money. Plant these special corms in an established garden bed with amended, well draining soil. Soil should be loose and crumbly and relatively free of weeds. Anemones and ranunculus prefer at least 6 hours of direct sun per day, so make sure you choose a relatively sunny plant without too much competition or shade from more established plants.

Anemones and ranunculus grow from corms. Many people refer to them as bulbs as shorthand for the dense underground storage organs. Bulbs and corms are both types of geophytes, along with rhizomes and tubers.

The main difference between bulbs and corms is that bulbs have layers of tissue that correspond to different areas of plant growth, whereas corms tend to be more dense. That might be more information than you really need, but it will help you understand why anemones and ranunculus (corms) look so visually different from tulips and daffodils (bulbs).

Start with Your Spot

While you're waiting for your corms to arrive, scope out your spot. You'll need about 36 square inches per corm. Choose an established garden bed with amended, well-draining soil and at least 6 hours of sun per day. If standing water pools up near this spot, choose a different one. Good drainage is imperative for growing anemones and ranunculus.

Soil should be loose and amended with an all-purpose fertilizer and aged compost. Don't use fresh manure or anything that could be "hot" with too much nitrogen or herbicides.  (If you get horse manure from a farm that sprays glysophate on its weeds, the manure could contain glysophate.)

Decide When to Plant

I grow ranunculus and anemones in zone 7b, so I have mild conditions for most of the winter. I begin planting anemones and ranunculus in November, and I continue until early March. Remember, anemones and ranunculus like cool soil -- no hotter than 60 degrees. If you plant too late and the soil gets hot while they're growing, they won't bloom. A soil thermometer is a good investment.

If you don't want to plant in fall -- because you'll  have to protect your anemones and ranunculus during cold snaps -- save your corms in a cool, dark place until you're ready. I don't recommend planting any later than early March no matter where you are, although remember, I know nothing about Northern climates. (I'm in North Carolina.) Look for local resources such as your state cooperative extension to help you understand your unique conditions.

Prepare Your Corms

A few weeks before you're ready to plant, soak your corms in water for about eight hours to hydrate them. If you have an aquarium bubbler that can oxygenate the water, definitely use it! Keeping that water oxygenated will help prevent rot in the corms.

After soaking, we use drenches to help prevent rot later on. These drenches are like probiotics for plants. They contain good bacteria and fungi that will fight off bad bacteria and fungi. The products we use are called Actinovate and RootShield. The small packages of these products have been largely discontinued,  but you might be able to find some.  Just be sure to check the expiration date before you buy since they expire quickly.

Once your corms are hydrated, you can choose what to do next! For home gardeners, I think you're better off planting at this stage. However, we presprout our corms to ensure viability and protect them from rot at the early stage. You can definitely try this!

We add a layer of sterile, damp potting soil -- just an inch or two -- to a plant tray or crate. A box or Tupperware bin would also work. It's important that the soil is just barely damp. If you squeeze it and water comes out, it's too wet.

We lay the hydrated corms on the soil pointy side down. Then, we layer another layer of lightly damp potting soil on top. Just an inch or two.

Tuck the box into a cool, dark place for about two weeks. 50 degrees air temperature is ideal. An unheated garage or basement is perfect. Just make sure it's not too cold (a fridge) or too hot (a warm room). We've sprouted anemones and ranunculus in a drafty foyer, and it's worked just fine. 

Keep an  eye the soil. You don't want it to dry completely. Misting with water every couple of days could be a good idea. We like to mist with a backpack sprayer. 

You'll know they're ready when little white roots emerge. They remind me of a Koosh keychain. You know, the rubbery pom-pom?

Keep an eye out for rot, which looks like white marshmallow goo at this stage. If you see rot, your conditions were too wet, and the corms have spoiled.

Put Them in the Ground

Once you've prepared your corms, you're ready to plant! Bury them in your chosen spot about an inch or two below the surface of the soil. When I say an inch, I mean that the top of the corm should have at least an inch of soil on top of it to protect it. Your hole is probably going to be 2 or 3 inches deep to accomplish this depth, depending on the size of the corm.

Lightly press the top of the soil to keep it from blowing off.

While They're Growing

Anemones like a drink once the air temperature is in the 50s and 60s. During the depths of winter, when it's colder, they don't need much water. Allow them to dry out between waterings to prevent rot.

When it comes to cold, remember that plants don't super know the difference between 38 degrees and 52 degrees -- they're good anywhere in that range. However, they DEFINITELY know the difference between 38 degrees and 31 degrees. When water transforms from liquid to solid, it can be traumatic for plant tissues. Anemones are very hearty, and they can tolerate temperatures in the high 20s with no issue. Ranunculus are more delicate, but a light freeze won't distress them.

However, once temperatures drop into the mid-to-low 20s, you want to think about protection. Agribon fabric is our favorite helper. However, if you use fabric or plastic to protect your plants, make sure you use stakes or wire hoops to prevent if from touching the leaves.

Troubleshooting

If you see black or brown growth on the leaves, you can pick them off. White mold is also a really bad sign. Preventing your anemones and ranunculus from sitting in wet soil is going to be the best way to prevent disease.

Your plants are likely to get a little spotty at some point, particularly if you live in a humid place like we do. Increase air flow by preventing weeds and decrease water. We don't really intervene beyond that. Don't freak out.  They'll probably be fine. Or they'll die. That's farming.

Blooms

Anemones and ranunculus bloom spectacularly. It's great to leave them in your garden to enjoy. They last a long time on the plants.

If you want to harvest the blooms, wait until the anemones have opened and closed one time, and then cut them at the base.

For ranunculus, allow the petals to soften and fluff out just a little bit, like a marshmallow. You don't want to cut them when they're super tight; however, don't wait until the petals begin to unfold fully. 

If you're not sure about the right stage of harvest, try some different options and monitor the results. See what works best for you!

When It's Over

We grow anemones and ranunculus as annuals. We remove the spent corms each year. You can leave them in the ground and see what happens if you like! Whether they return will depend on your drainage.