Q: In a previous question/answer you said that the Rose Verbena was short-lived as perennials go. What do you mean by short-lived?
A: In some settings, rose verbena may not survive more than a couple of years. It likes sunny, well-drained conditions.
Q: Is it totally too late to plant your svanna wildflower seed pack?
A: Most of the seeds in the savanna seed mix need a cold moist period (stratification). Ideally, the seeds should be sown between November and late January.
Sometimes, rose verbena will germinate without stratification, but a minimum of two weeks stratification (or ideally 4 to 6 weeks) will greatly increase the number of seeds that germinate. You can do this in the refrigerator by mixing the seeds with some moistened sand or potting soil and chilling them for the appropriate amount of time.
Q: Is this an invasive plant?
A: It can spread a little by seed.
It is a sprawling plant, and it can grow roots from where it's stem lies on the ground. This means that it can slowly expand its original territory from where it was planted. By those standards, you could say that it spreads. I wouldn't go so far as to call it "invasive".
It is also a fairly short-lived plant as far as perennials go.
Q: What would be a good alternative to this?
Q: What is the hardiness zone for your rose vervain?
A: Our plant stock is from central Missouri. Missouri Botanical Garden lists it in zones 5 - 9. Here is the link for more info: http://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=f204
Q: Is this plant deer and rabbit resistant?
A: Its bitter leaves should deter deer and rabbits. If they do nibble it, it should be fine and will send out new growth fairly quickly.
Q: Is this a good container plant in Zone 5 (Des Moines, IA)? For example, wild petunia and little bluestem are growing well in my containers without watering.
A: Rose verbena isn't a strong perennial, so it likely won't survive the winter in a Zone 5 container. However, it will be fine in a container during the growing season.
Q: Does verbena canadensis benefit from cold moist stratification? I f so for how long a period?
A: Fresh seed often germinates within a month or two after sowing in June or July; additional germination will occur the following spring.
Stored seed should (probably) be cold-moist stratified for at least 30 days.
My records (going back to 2011) show that there is almost always some germination, but there isn't a "best method". Stored seed sometimes germinates fine with 60-100 days strat; sometimes it germinates poorly. The same story with fresh seed and no strat. One possible variable might be how well each seed lot was cleaned; poor germination might be due to a high volume of non-viable seed. Either the plants didn't get pollinated very well, or we didn't clean the seed well enough (probably a combination of both).