At a glance:
(most of these are for common sunflower, Helianthus annuus)
- Soil needs: Accepts many types, but it must be nutrient-rich and well-drained. A very good plant for restoring soil, too.
- Water needs: Medium water needs once established, about 1 inch per week. Keep soil moist when they are still very small.
- Sun needs: Full sun… it’s in the name!
- Size needs: As far as flowers go, almost none larger. They can get over 10 feet tall. But they are only an annual, so no harm in experimenting!
- Wildlife value: Extremely high. A keystone species, absolutely adored by bugs and birds alike. One of the best annuals you can plant, if you have the space – your garden will be buzzing!
- A note on transplanting: Everywhere online will tell you that transplanting sunflowers is hard, and they are better as direct-sow. This has not been my personal experience. I have the greatest rate of success when transplanting them at about 6-8 inches tall.
- A note on native range: There are many types of sunflowers, native all across North America. However, the stereotypical common sunflower is presumed to be native to mid-west and western North America. This range has been difficult to determine for certain, because it has been naturalized all over the continent for a long time, due to domestication by Native Americans. Because of this, I personally see no problem planting them in the east.
A bit more…
What more needs to be said about the mighty sunflower!? Well, actually, there is plenty. For starters, depending on where you live (and what species we are talking about) they may not actually be native… including where I am giving them away! Scientists are still debating the original native range of the common sunflower (Helianthus annuus). Some say western North America, some say as far east as the Mississippi. But no one says it’s native to the east coast. However, it has been living all across the continent for thousands of years due to cultivation by Indigenous Americans. It has naturalized without becoming invasive, and supports loads of pollinators and birds that are native, so I personally think they are okay to be planted in a native garden.
Yet it must be noted that some species are actually considered invasive in certain states. For instance, Helianthus annuus is considered invasive in Iowa (and other areas of the plains, I think). There are also a few sunflowers considered invasive on the east coast, such as Mexican Sunflower, and Ozark Tickseed Sunflower. However, neither of these are members of the Helianthus genus — they are Tithonia and Bidens, respectively. To my knowledge, there are no Helianthus flowers that are considered invasive in the north east.
One of the Helianthus considered truly native to my area of the northeast (New Jersey) is the thinleaf sunflower (Helianthus decapetalus). It is a woodland sunflower that thrives in difficult areas such as bottomlands, wet swampy areas, shady areas, riverbanks, etc. This makes it perfect for my personal property, and is something I am eagerly trying to propagate in numbers. I have not succeeded yet, but when I do, it will certainly be a plant I seek to give away. It attracts innumerable amounts of insects and birds, and is host to several too, such as the painted lady (Vanessa cardui) and the silvery checkerspot (Chlosyne nycteis). Stay tuned to hear more from me about this plant in the future, hopefully!
Two other similar sunflower species native to New Jersey are Helianthus divaricatus (woodland sunflower) and Helianthus strumosus (paleleaf woodland sunflower). These both are notably different from decapetalus in that they tend to inhabit dry woodland areas rather than moist, swampy ones. Yet another sunflower native to New Jersey is Helianthus giganteus, or the giant sunflower. This one is a bit more similar to the typical common sunflower, and more suited for a curated flowerbed. The ones discussed above were “woodland sunflowers” meaning they tend to found more in forests or forest edges. They also tend to be smaller. The giant sunflower, on the other hand, can grow quite large, to match most peoples preconception of a sunflower. Although this mostly applies to growth habit, not the specific blooms — the blooms are smaller than cultivated Helianthus annuus, but there can be many per stalk. All in all, it is a beautiful choice, and (along with the rest of Helianthus) supports more pollen-specialist bees than any other genus, with the exception of perhaps Solidago.
Of course, the common sunflower is a valid choice too. They are readily available, and in stunningly beautiful and diverse shapes, sizes, and colors. While not truly native (if you are reading this from east of the Mississippi), they have been here for thousands of years and proven themselves to not be invasive. Just like the other Helianthus members, they still support the pollen-specialist bees which are native, such as Andrena aliciae (yellow faced miner bee), Andrena helianthi (sunflower miner bee), Perdita bequaerti (Bequaert’s miner bee), and many others. And they still support the native birds, too. One of my favorite garden memories is looking out my window at a sunflower patch, my attention having been caught by some subtle movement. At first I couldn’t discern anything, until I noticed that each and every sunflower had at least two goldfinches atop it, looking for seeds, blending in with the golden blooms. It was a beautiful sight, and that memory alone will drive me to plant sunflowers every year without fail!
