How To Grow Saffron: Research Farm To Home Garden
by Amanda
Researchers at the University of Vermont are growing Saffron Crocus corms to study the crop as a possible revenue source for small farmers. This technique translates beautifully to the home garden!
How to Grow Saffron At Home
This September, American Meadows donated 1200 saffron crocus corms to researchers at the University of Vermont, who planted nearly 3,500 total in a hoop house in Northern Vermont. I met with Arash Ghalehgolabbehbahani, a post-doctoral research candidate at the University, to get great tips on how to grow saffron crocus in the home garden. I wanted to find out how to adapt his practices and experience thousands of crocus in bloom!
Saffron Crocus: An Unlikely But Promising Crop
One of the first questions I had for Arash is why research saffron? Arash is from Iran, a big producer of saffron, and he says he noticed climate similarities between his home country and Vermont. This led him and his colleagues to explore growing saffron on a large scale as a second season crop for small Vermont farmers.
The research lab at the University of Vermont where last year's corms, stigmas and petals are being studied.
Saffron is a purple fall-flowering crocus that is extremely easy to grow and should be planted in the late summer for blooms in just weeks. It yields the rust-colored, edible spice.
Arash says their research is two-fold; they are examining the best way to grow saffron crocus in a large-scale setting in the cold Vermont climate, but also looking at the quality of saffron corms from several different producers. The 1,200 corms we donated to the study were originally grown in the Netherlands. The other 2,300 corms came from Vermont and Pennsylvania.
This saffron corm has sprouted roots and is just a few weeks away from blooming.
Saffron Corms: Food, Flowers, or Medicine?
I always associate saffron crocus with the expensive spice, which is what I’ve grown them for in the past. But Arash explains that the big money isn’t in the spice, which is rarely used, but in the medicinal properties of the chemicals found in the saffron stigma.
The most expensive part of the saffron bloom are the chemicals extracted from the stigmas, which are used for medicinal purposes.
The three chemical components that are measured in the stigma are picrocrocin, crocins and safranal, Arash explains. The higher level of these chemicals in the stigma, the better the quality. “[These chemicals] are very valuable and they have anticarcinogen effects, so they are really expensive,” he says. “In each gram of saffron, you can find 7 milligrams of picrocrocin and each milligram of picrocrocin can cost $300. So it is very expensive.” Arash says that scientists are exploring the use of picrocrocin as an alternative method of treating cancer.
Growing Saffron Crocus in a Hoop House
Bob Roberts, a farmer and environmentalist in Northern Vermont, donated his land and hoop house to UVM researchers to grow the saffron corms. Bob is particularly excited about saffron's potential ability to cure disease.
Arash says that although many plant saffron directly in the ground, they’ve had better success with planting the corms in milk crates. “We had a lot of problems with rodents last year; moles, voles and mice,” he says. “When you plant the corms in the crates the rodents cannot come inside of the crates because we have weed cloth there [which] works for protecting the corms.”
UVM's saffron crop being grown in Bob Robert's greenhouse in Northern Vermont.
Another benefit to the crates is that they are moveable, making it easy for farmers to bring them inside the hoop house after the preceding summer or fall crop has finished. “After the growth season you can bring [the crates] back into the greenhouse. With this method we will have two growth seasons instead of one in high tunnels,” explains Arash.
Two (and even three) growing seasons per filed or hoop house is of high importance to farmers, as it means multiple income streams from the same piece of land.
How To Build a Rodent-Resistant Container For Growing Saffron:
- Get weed cloth, milk crates and duct tape from your local hardware or garden center.
- Cut two pieces of weed cloth that are long enough to overlap the edges of the milk crates.
- Place the first piece of weed cloth in the crate and tape the edges.
- Place the second piece of weed cloth in the crate and tape the edges.
- Tape around the top outer edge of the milk crate to secure the weed cloth.
Step-by-Step Instructions For Growing Saffron Crocus in Crates or Containers:
After Arash showed me how to create the milk crate planter, he walked me through the step-by-step process of planting and growing saffron.
- Whether you are planting in the ground or containers, make sure to have regular topsoil (garden soil) and some compost or potting soil.
- Add about 5” of topsoil to your crate or container before planting corms.
- Plant 11 corms per square feet (each milk crate), making sure each corm is about 2.5” from another. Arash planted them in three rows in the milk crates.
- Plant the corms with the pointed side up. If you can’t decipher which end should go up, plant the corm sideways. It will find its way.
- Cover the corms with 2-3” of regular topsoil.
- On top of this soil, add another thin layer of compost or potting soil. The nutrition gradually releases into the soil and helps the saffron grow. Another function of this is to help suppress weeds, acting as a sort of mulch.
- Water thoroughly immediately after planting.
Ready to grow!
Arash explains that the initial watering is extremely important because that is what helps break the dormancy of the corms. After that, you only need to water the corms every 15 days. “Coming from an arid and semi-arid areas, if you water the saffron a lot fungi will damage the saffron corms,” says Arash. “The greenhouse I am planting these at is like a desert. Moisture is not good for saffron.”
Saffron appreciate sandy, loamy soil and won’t thrive in clay soil, says Arash. He also stresses that the bigger the corm, the better. “The size of the corm is really important,” he says. “Based on research, the weight of each corm has to be at least 5 grams.”
Adapting This Method Of Growing Saffron At Home
Arash and I talked about how to adapt this method of growing saffron for the home gardener. He explained that it’s basically the same process, regardless of the scale and amount of corms being planted. Home gardeners can use milk crates or containers to help deter pests and to control the environment in which they grow their corms. So whether a home gardener is looking for late season color, or harvesting the flowers for potpourri and spices, there should be a higher success rate when planting the corms in containers.
Results At The Greenhouse
I visited Arash up at the hoop house in Northern Vermont about six weeks later to see how the saffron crocus were coming along. He told me they started harvesting around mid-October. Like he suspected, the corms in the milk crates did much better than those planted in raised beds.
Arash says the saffron corms planted in milk crates did better than those planted in raised beds.
Harvesting Saffron
Every two days Arash comes up to the hoop house to harvest the flowers. The harvesting process doesn’t require a step-by-step list – you simply pick the flower from the stem with your fingers. The stigma (which is red), stamen and petals are also very easy to separate by hand.
The stigma, petals and stamen are easy to separate with your hands.
After harvesting the flowers, Arash and his colleagues separate the stigma and stamen and send the stigmas to Mississippi for chemical analysis to compare the levels between Pennsylvania, the Netherlands and Vermont.
Different Uses For Saffron
“The saffron petals are also valuable,” says Arash. “In Europe they are developing some type of medicine for animals from them. I’m trying to keep the petals but it’s really tough because you have to dry them perfectly or else the fungi will get to them.” He adds that the United States often uses the petals for potpourri. I never thought of Saffron as overly fragrant, but he proved me wrong with the box of freshly harvested flowers.
The saffron petals are used to make potpourri in the United States.
Arash says that even growing saffron in the small hoop house in Northern Vermont can be profitable for a small farmer. “The United States is the biggest consumer of saffron in the world,” he explains. “And they are hardly using it as a spice, they are using it to produce medicine. Compared to tomatoes and other conventional crops, saffron can produce more money for farmers.”
Arash says he enjoys days he comes up to the hoop house to harvest.
The key for farmers – especially in colder areas like Vermont – to growing saffron crocus is that they can start the production after the conventional crops have finished for the season.
Arash can’t stress enough that saffron crocus is a tough, hearty crop that doesn’t need much attention, which makes it so special. “They are just so beautiful. I enjoy harvesting days very much,” says Arash. I couldn’t agree more.
