Lobelias are the ultimate “easy-win” for any gardener. They’re super low-maintenance, but they reward you with a massive explosion of color. While they’re happy to do their own thing, giving them just a little bit of extra TLC can really take their growth to the next level. One of the best ways to do that? A quick trim now and then.
Does your Lobelia actually need a haircut?
Whether or not you need to grab your garden shears really depends on how you’re growing your plants. First off, consider the variety. Lobelias generally come in two styles: mounding (upright) or trailing. The mounding types grow like a dense groundcover and usually don’t need much pruning. However, if your trailing varieties start looking a bit too “leggy” or long, it’s time for a trim.
You also have to look at whether your Lobelia is a perennial or an annual. If you have a perennial variety, you’ll want to cut it back to about a hand’s width above the ground in the fall. For the annuals? Honestly, don’t sweat it. Once the season is over, just dig up the root ball and toss it in the compost.
Another reason to prune is to stop seed production. If you don’t want your Lobelia spreading seeds all over the place, you’ll want to deadhead those faded flowers pretty quickly.
Pro Tip: If you spot any pests or signs of disease, don’t wait—snip off those affected areas immediately to keep the rest of the plant healthy.
Why pruning is worth the effort
While you don’t *have* to prune a Lobelia, there are some major perks if you do. If you’re like me and want as many of those gorgeous violet-blue blooms as possible, this is the secret.
Typically, Lobelias have their big show from May to June. I know it feels wrong to cut back flowers while they’re blooming, but trust me, it pays off. If you trim them back during this time, the remaining blooms will actually last longer. Plus, you’ll often get a second “bonus” bloom phase from September through October!
Pro Tip: Intense direct sunlight can dry out the fresh cuts on your plant. Try to pick a cloudy day for your pruning session to keep the plant happy.
How to prune like a pro
Here’s your quick checklist for a successful trim:
- Always disinfect your cutting tools first.
- Snip off any wilted flowers or dead stems.
- Feel free to cut the plant back by up to two-thirds of its size.
Pro Tip: Don’t be afraid to be a little aggressive! Even if you cut back two-thirds of the plant, you’ll usually still have about 3 inches of growth left, and it will bounce back stronger than ever.
