Alright, on to the next weed in the series! Here’s another easy one to identify and control. Meet prickly lettuce (Lactuca serriola).
Prickly lettuce is a very common weed in Colorado landscapes. It’s called prickly lettuce because it’s a close relative to the lettuce that you and I often eat, plus each leaf has prickles on the underside along the central vein. It is not a pleasant plant to brush by if you’re wearing shorts.
It has one central upright stem, which often has prickles, too. The stem can be green or even reddish purple. If you break the leaves off the stem, you’ll notice a white sap. I made a quick one-minute video that shows you how to identify prickly lettuce.
I often see prickly lettuce in areas where there is bare soil or rock mulch. It will also show up in cracks in the sidewalk or driveway. It’s a pretty noticeable weed, so it’s easy to spot. Sometimes it will grow in the middle of your flowers or shrubs. It can go undetected until it pokes its top up through your landscape plant.
Prickly lettuce grows very quickly in spring, reaching heights of 2 to 5 feet tall. Just like horseweed, it will produce a ton of seed if you let it flower later in the summer. Therefore, it’s a good idea to control it while it’s still small and manageable.
Because it germinates in the spring from seed, it’s another easy weed to pull by hand. Even though it can be pretty tall, its root system is pretty small. The central stem makes it a piece of cake to yank out of the ground in most situations.
There are sometimes when prickly lettuce will grow in a crack of concrete that makes it really hard to pull out for some reason. In this situation, if you pull it and the stem breaks, it will often leave a very small stump of stem and a few ugly leaves. It’s really hard to pull out when it gets to that point. It will continue to grow and produce leaves close to the ground. When this happens, I go ahead and spray it with a weed killer to get rid of it. So, my strategy is to hand pull first and spray only if the stem breaks making it impossible to pull.
Unlike horseweed which you can pull barehanded, be sure to use a pair of gloves when working on this one. The prickles will irritate your skin and the sap can be very sticky.
When you get a chance, be sure to grab some gloves and scout your yard for prickly lettuce. If you have enough, you might even be able to invite your neighbors over for some prickly salad.