Lisianthus
Overview:
Lisianthus are one of Phoenix best kept secretes! These flowers take the heat, and will actually last a few year with proper care. They are a rose like flowers and come in an array of colors. They are versatile flowers making them great to grow for cottage gardens, containers, and cut flower arrangements.
Adventure Level
2/5
Starting seeds:
If you are looking to start these beauties from seed, patience is key. Start them inside under grow light sometime in between Thanksgiving and late January here in zone 9b. Surface sow two seeds per cell and lightly top with fine vermiculite. These seeds are prone to dampening off so make sure that they get good air flow post-germination. Start them 10-12 weeks before your last frost in colder areas. You fall plant them if you would like to start seeds in late summer in zones 9 and warmer. They will not bloom until the following spring.
When to plant outdoors:
You can plant in the spring as well as the fall (in zone 9 and warmer). Fall planted lisianthus will bloom the following summer. Spring-planted lisianthus will bloom that same summer. Lisianthus like to get established when soil temperatures are still below 60 degrees, so don’t wait for to long to plant them in the spring. If planted late, plants may bloom on short stems ( only applicable for hot cliamtes). If that is the case, the plants will still over survive the summer, over winter and bloom the following season.
Pinching:
Pinch the plant to help encourage branching. This will allow the plant to send up side shoots so you can get 3-5 bloom stalks per plant. I usually pinch my plants 1-4 weeks after planting depending on the plug. Once the lisianthus starts to put on lateral growth is a good time to do so. Pinch above the 2nd or 3rd leaf set.
Spacing:
3-4” apart
Sun:
Full sun, 6 or more hours per day.
Water:
Lisianthus like consistent moisture. Make sure they dry out between watering to avoid root rot. When watering try not to get the foliage wet. Containers are watered 2x per day during the hottest months in Phoenix. In-ground they are watered every day.
Flower Support:
I would advise using support if you intend to use these for cut flowers. In containers and small garden spaces, Peony cages are my favorite support method. If growing in beds, you can use Hortnova netting. Shop John’s favorite peony cages here.
Fertilizing:
Lisianthus are heavy feeders, feed them consistently with a weekly liquid fertilizer. In the summer we are watering plants a lot more and nutrients get leached out of the soil more quickly. This means that we need to be applying fertilizer on a more consistent basis to make for the constant leaching. You can find our favorite fertilizer here.
Succession plant?
I do not typically plant many successions. I like to plant all my lisianthus in March and April.
Post-summer care:
After the summer the plants can be cut back and left alone. Trim back any dead or diseased stems and keep on keeping an eye on it throughout the winter. Make sure that they aren’t getting too much water during this time as they can be susceptible to rot. Once you see new growth emerging in late February / early March, give it a good feeding and wait for them to green up.
Favorite Varieties:
Arena Apricot
Rosita ‘Red’
Voyage ‘champagne 3’
