Climate Zones will tell you if you are in an area that is likely to change your annual into a perennial. Out here on the West Coast where our temperatures are rather mild most of the time, Zone 9, several annuals will behave just like a perennial.
A good example of this would be Vinca and Impatiens. These plants are opposites when it comes to where you would plant them. The Vinca loves full sun and them Impatiens loves the shade which is a great benefit if you want to add some vibrant colors to those darker areas of your yard.
The Vinca comes in both an Annual and a Perennial variety. Last year in the spring, I planted about three six packs of the Annual variety of Vinca. So far they are still growing well and getting larger and fuller as each month passes by. The variety that I have is producing seed pods that are now opening up and dispersing about 2 dozen seeds per pod. Each plant has at least 25-50 seed pods!
The seeds will produce new plants so I am picking up as many seeds as I can and storing them away so that I can plant them later. This is a great way to propagate some of your favorite plants. If these seeds are picked up the Vinca will grow where ever it falls! You may not want to have a Vinca growing out the crack in your side walk!!
Several varieties of plants will produce seeds which will allow you to propagate your own plants. The Day Lilly is another of the plants that will also produce viable seeds that you can harvest, store and use to produce more of the same plant. Alyssum will produce a prolific amount of seed but usually scatters around so much that it is hard to collect it. I can remember planting white alyssum in my front yard. Usually in the fall it would start to look rather shabby and scraggily so it would pull it out, shake the seed off onto the ground and in about 7-10 days, I would have new Alyssum growing in my planter.
I also have a lot of birds in my neighborhood and the birds have enjoyed feeding on the seed and crawling through the Alyssum. As a result, the seed would also stick to their bodies. Birds being birds, they would fly to the backyard as well and visit my other container plants, dropping off seed in the process! I then had Alyssum in my back yard in places I did not plant it!!
Once the Alyssum has started to grow, I found it difficult to transplant it to a more desirable spot. Not wanting to harm the plant, I let it grow and would then harvest the seed later by carefully pulling the plant out of the ground, trying not to shake any of the seed off. Did this work? Well, sort of meaning that I did get seed to the desired area but I still had plants coming up in odd places. Ah such is Mother Nature, beautiful and unpredictable.
Depending on what area you live in the variety of plants that produce seeds will change. The nice thing about this is that you have nothing to lose and everything to gain! Have fun with your planting adventure!
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