Everyone's favourite cut flower... and if it isn't, it should be!
Ok, it's alright if it isn't your favourite, but it's by far one of the best cut flowers you can grow in Manitoba. It's long lasting, beautiful, delicate yet resilient... what's not to love?! It was my mom's favourite flower since the day she discovered it decades ago (fun fact we were among the very first to start growing it), and it will always be my favourite because it reminds me of her.
Lisianthus sounds great right? Yes, but there's a catch. Growing Lisianthus isn't all fun and games. In fact, although it's amazing as a cut flower it is a challenge to grow, and I don't recommend that everyone should grow it.
Every year people ask about growing Lisianthus and here are my two cents about it. If you are a beginner gardener and you want to try Lisianthus, you should! BUT, you should buy the plants from a local garden centre. My favourite recommendations on where to buy are from Lily Stone Gardens (located in Rosenort MB) or from Ron Paul Garden Centre (located on St. Mary's Road just outside the perimeter). Purchasing plants from a local garden centre will give you a head start on the growing season, and will allow you to skip the most difficult part which is starting them from seed. More on that later.
Lisianthus are stunningly beautiful, and most plants if pinched will produce between 2 and 4 stems of flowers with multiple blooms. If you do not pinch them (trim them back early) you will have blooms sooner, but you'll often only get one stem of flowers per plant. That means if you hope to fill a garden space you'll need LOTS of plants. If your aim is to have a showy garden, there are flowers that do a better job than Lisianthus. I personally don't think they are very showy in the garden unless you're growing a huge patch of them. However, if you're growing your own cut flower garden, be sure to add a few Lisianthus! Lisianthus take a very long time to re-grow, so if you pick off stems of flowers, you will often not get more blooms in our short season. If you do get a second flush, they will always be shorter and less showy.
It's important to note that Lisianthus take a very long time to mature and they grow very slowly especially for their first few months. It's typical for them to take 175-250 days from seeding for them to bloom. Thats 6-8 months! That means if you are starting your Lisianthus from seed in Manitoba, you have to start them in December or January in order for them to bloom before frost. If you want to give starting your own Lisianthus a try, here are my tips.
Purchase your seeds from a reputable source. I like Johnny Seeds. They have a great selection, and great germination percentages. You will also need a proper set up to start highly intensive seeds. You will need heat mats, and grow lights/fans on a timer. You cannot grow them from seed without them. I like to start Lisianthus in 11x11 trays in rows covered lightly with vermiculite, and sprinkled with cinnamon to deter algae growth. My specific seed starting method is the same for Lisianthus that it is with all my other seeds, and I have a blog post dedicated to starting seeds for more on that. Lisianthus require 16 hours of daylight for gemination and growth, this is why grow lights are incredibly important. I have ours on a timer so that I never have to worry about it. I also have them on heat mats so that the soil and plants stay at a constant temperature. They typically will germinate in 10-15 days when the soil is between 20 and 22 degrees Celsius. It's very important that the soil does not dry out prior to germination. This can be tough especially with all the heat going on, so it's important to check the soil moisture daily. The soil should be moist, but not drenched... having this balance is crucial. To help the soil from drying out, it's best to have a plastic dome cover on the plants until at least 50% of the seeds have germinated.
Once you have germination, let them be until you have plants that have at least 4 leaves, and are about the size of your pinky nail. Once they are this size it's important to transplant them to give them a little more space. This is where they'll stay until it's time to plant them outside. I find they do best by keeping the temperature under 22 degrees at all times. They don't love higher temperatures until they are larger plants. Once I move them into our greenhouse in March they will experience warmer temperatures and that is completely fine. Like most flowers, they do not like the nighttime lows to dip too far. I don't allow our greenhouse to fall below 12 degrees. This of course is already a few months in to growing. Prior to this, they should stay around 20-22 degrees at all times.
Once you have established plants, they grow well. When you transplant them they will slow growth initially but then shoot up and grow much quicker once that phase is over (usually a week or two). I like to plant my lisianthus very close together to avoid needing to support them with staking or mesh. If you are growing them as a garden or potted flower and not a cut flower, you can choose varieties with shorter stem length to avoid having them fall over. Lisianthus are slightly frost hardy, and can handle cool temperatures in the fall, but their growth rate will slow significantly as the day length shortens. Be sure to plant them in full sun, to maximize their growth. They do best in fertile well drained soil. They are susceptible to some root diseases, so applying Rootshield is recommended in some cases.
Once planted in the garden they will require water based on your soil and the temperatures. When watering, give them a good soak. Then allow them to dry out between waterings, and if possible water at the root not overhead to avoid damaging stems and flowers.
As a cut flower you can expect a vase-life of 10-15 days, but sometimes even longer. It's not uncommon for clients to say they have theirs for 3 weeks. I recommend picking them when it's the cool of the day (either morning or evening) and when the plants are dry (no dew or rain).
I hope this helps you understand some of the needs and requirements of growing Lisianthus. Maybe it even gives you a better appreciation for their beauty. Happy growing!
M
