>>Recently the USDA has changed its hardiness zone map.

What does that mean, and what does that mean also for public gardens such as here at Lewis Ginter?

>>Yeah, well, thanks for being here.

The USDA changes that every 30 years based on the data, and it's looking at the minimum cold temperatures.

And that means our area here in Richmond, we're actually a zone warmer than we used to be.

But this doesn't encapsulate everything that we should be thinking about or the kind of the larger issue at hand of climate change.

The hardiness zone map is a great way for gardeners, horticulturists, and agriculturists to kind of help identify and select the right plants for their place, but we should also be talking about heat tolerance.

And so I think there's a opportunity even within those two subjects to talk about microclimates, storm water, and the rainfall, and how that's changing in addition to changing temperatures.

But probably one of the more exciting silver linings to this kind of bigger discussion is plant selections, specifically around zone pushing, and to your original question about the USDA hardiness zone map.

And so there's some really great opportunities that we can talk about here at the garden and our collections that we're starting to implement as we think about what plants we can be growing here for the future.

The first example I have is of this dwarf pomegranate here.

This pomegranate actually overwintered successfully this past year.

Last summer it fruited, it had these great little fruits.

There's actually some.

>>Yeah, you can see some of the seed pods leftover from last season.

>>Yeah.

Yeah.

This dwarf pomegranate is great for charcuterie boards.

I love throwing them in smoothies.

It's not like the big pomegranate that you see at the grocery store, but it has excellent taste.

And it's perfect for door yard, fruit tree, or small gardens.

>>And whoever knew you could grow a pomegranate in Central Virginia.

>>Right.

Yeah.

>>So are there any other examples of plants that's pushing the zone that you can show us?

>>Yeah, we have several examples.

There's actually a eucalyptus right over here.

It's a plant that we've had in the garden now for a couple years.

It's tried and true.

We know it's winter hardy.

We're actually kind of cutting it back and keeping a really healthy root stock so it always is able to come back even in the worst winters, but this winter we didn't even have to cut it back.

So this has a really great form to it.

It's more of a natural form, and that's kind of how we've pruned it.

But it's got beautiful silver foliage.

There's bright red new stems coming out.

Again, this is tried and true.

We're looking at adding this throughout the garden moving forward.

>>I hear your moving it out into the parking lot, so that's saying something about this plant and it's hardiness now.

>>Yeah, and really the parking lot, it's not just the winter hardiness there, but the overall exposure, dry conditions.

Plants have to be pretty tough to be in a parking lot.

>>Parking lot.

Exactly.

>>You wanna go take a look at another example?

>>Yes.

Let's go do some more exploring.

(birds chirping) >>So another thing that we have to think about as gardeners now the USDA zone has changed and the implications really just overall what it means to have a changing climate is pest and diseases in the garden and how that's gonna impact the plants that we're trying to grow.

And one that's actually coming to mind as we walk through the garden over to the rose garden is southern blight.

And so this past winter, you know, we didn't really have a cold winter.

In this spot here, we actually had some southern blight last summer.

So we're gonna have to closely monitor, make sure that the fungicide treatment that we did was effective, and that we're not gonna continue to have that spread.

>>Yeah, with the warmer weather, I guess the pests and diseases will continue on because you don't have that cold spell to knock some of that stuff out.

>>Yeah.

Yeah.

And there's some other examples of that in the garden that we can talk about as we're going through.

Well, Serome, welcome to the rose garden here at Lewis Ginter Botanical Garden.

This is another area that I wanted to show you.

You might be familiar that roses have quite a few problems, and that's translating over into how climate's affecting the garden and how we shape our collections moving forward.

>>I know we have a lot of black spot in roses, and then rose rosette has become a big issue here in the area.

>>Rose rosette is huge for us.

We do have the black spot too, but the rose rosette is really challenging because with the milder winters, the mites aren't dying back the way we would normally see them.

And the leaf buds and the roses are pushing sooner and sooner.

And one of the ways that we're trying to combat this is a mix of both chemical application and cultural application.

So as you look across the rose garden, you'll notice that there are some herbaceous perennials that we've added.

We've also tried to break up the groups of roses to create a little bit more air flow and separation between the varieties.

>>Have a little more biodiversity in the plantings.

>>Exactly.

Exactly.

As we're looking at the lake here, another aspect that we can talk about is observation that we made this spring with algae.

With the changing temperatures and climate, we've noticed that we had a more severe algae bloom much sooner than we were expecting.

And when we were talking to our company that helps us treat algae, they were finding the same thing all across town.

And so it was really hard to get them to help come out and treat the algae for us this year.

So we just walked by a needle palm, and that made me think about our palm collection over in the conservatory in that conversation around zone pushing plants.

The needle palm is hardy for zone seven, but it really just makes me want to challenge the notion of what kind of palms we can actually put out in the landscape.

>>Oh, wouldn't that be nice?

>>It would really kind of add a whole nother element to garden design.

But one of the things that I wanted to show you over here is this magnolia.

This is Magnolia figo or the banana magnolia.

And the reason I want to show you it is it doesn't look very happy, and it kind of ties into that conversation we've had about cold hardiness isn't the only factor when thinking about plant selection.

We talked a little bit about microclimates.

This tree does have a really great microclimate.

It's got a wall.

>>It's got a wall providing some shelter for it.

>>Yeah, but one of the challenges that it's having is actually moisture.

The garden beds that we're standing on are so squishy, and actually they're standing water here.

>>So it's not enjoying the wet feet.

>>Yeah.

Yeah.

So there's something about that combination between it being cold and water that the plant can't tolerate.

And interestingly enough, we actually have another magnolia fig just right over on the opposite side here mirroring it, and it's in full bloom, and the leaves are nice and dark and green.

There seems to be better drainage over there.

So we'll have to do something as we work in this garden space to try to improve the drainage so that this tree can thrive.

So now we're over in the Grace Arents Garden.

This is a historic garden, and we always really try to celebrate the legacy of Grace Arents with really intentional horticulture designs.

But with some of the conversations that we've had around climate change and the zone changes, we've actually observed some of that impacting the horticulture displays here, where our tulips were actually blooming way too early, like weeks and weeks ahead of time.

Some of the daffodils hadn't even started coming up yet.

But we're very fortunate it did cool back down.

>>So with the climate change, it is making it harder and harder for the plans to really work out?

>>Yeah.

Yeah.

And we think really carefully about our plant selection.

And you know, just knowing that two weeks every spring is gonna be 70 degrees, it makes it a lot more difficult to really predict what's gonna happen with these displays.

>>Well, I wish you could just have a magic ball and be able to determine that to make everything work out.

But I do appreciate you having us, and what a lovely display it did turn out.

I'm glad we got to get here and catch this nice view.

>>Thank you so much for coming out.

I really enjoyed talking with you about the new USDA zone map and what that means for how we garden in the future.

Everything from our plant selection and zone pushing to the impacts of pests and disease in the garden space.

>>Well, with everything changing as gardeners, we all must change with it, so we will have to work with what we have.

>>Isn't that true?