Is it Safe to Plant Summer Annuals?

You would think so, given that the garden centers in the big box stores are bursting with blooms. Two weeks ago, most of this bloom was from spring-blooming perennials and annuals like phlox and dianthus and snapdragons, but in the last week, tender summer annuals have appeared in great numbers. Is it time to plant summer annuals like salvia, zinnia, vinca, and impatiens?

According to the National Weather Service, the "average" last freeze date is March 28. This means that there is still a 50% chance of a freeze occurring.  Another way to think about this is that if you list all the historical last freeze dates for Memphis by year in date order, half of them occurred before March 28 and half of them occurred after. The latest recorded freeze date for Memphis is April 16.

Another thing to think about before buying your tender summer annuals is that, even absent a freeze, these plants don't thrive in cool weather. They like warm air and soil temperatures and will sometimes just sit there until they get temperatures more to their liking. If a cold snap occurs, they might not die, but they might not fully recover either. One year, I bought annual salvia after a temperature dip. It looked a little stunted but I did not see any obvious tissue damage, so I assumed it would recover. But it did not grow, and I eventually replaced it.

So what should a gardener to do? We have an old family friend who never plants anything tender until after May 1. This is probably a good strategy in terms of plant health, but the best selection of plants in the garden centers is usually earlier than that. So I plan to wait until mid-April and shop at my favorite local grower. (Local growers time the availability of their plants to be more in line with the best planting times for the geographic area. So petunias might be available a few weeks before vinca is available.)

Don't be fooled by this warm winter and seemingly early spring. Weather forecasting is getting better but Mother Nature still fools us. Besides, it seems to have been an especially good spring for pansies. Why would anyone be in a hurry to replace something looking like this?

(And speaking of pansies, don't forget to fertilize them. Barring a heat wave, they'll perform for at least another month but they need to be fed.)

One final word: this discussion has been about setting out ornamental plants. If you are planting seeds of these same plants, that's another subject entirely.

Winter Blooming Iris

Over the past few years, I've been thinking more about adding winter interest to the garden. In some areas of the country gardening with "winter interest" means berries and interesting or colorful bark on trees. However, I've come to realize that in our area, we don't have to settle for only these features--we can have something blooming all winter! Think camellias, hellebores, edgeworthia, pansies, etc. 

And lately I've discovered that there are also irises that bloom in the winter. These are not the irises that many of us have that bloom in the spring and rebloom in the fall. I'm talking about irises that have their primary bloom period in winter. For instance, Iris reticulata:

and Iris unguicularis:

I would really like to add a few winter-blooming irises to our winter garden but I ran into two problems: availability and cost. I have been unable to locate Iris reticulata in stock at any domestic nursery. (They seem to be much more common in the United Kingdom.)  I'm going to check back in late summer with the domestic nurseries that had it, but listed it as "out of stock." I think these are usually planted in the fall so I may have better luck later finding them in stock.

The other problem was cost. I found Iris unguicularis on the Plant Delights Nursery website. It was $24 for a 4-inch pot. Yowza!! After considering for several days whether I wanted this plant that much, I decided to invest in a single starter plant. I rationalized that $24 wasn't too much to pay for a plant that would someday spread into a swath of plants that would make a major contribution to our winter garden. In the meantime, I would choose the location of the single little plant strategically so that I could see and enjoy it on cold winter days while I sip my morning coffee.

So I placed the order on the Plant Delights website, but when I started to check out I was stopped in my tracks by the shipping fee. The cheapest shipping was $21.25 ($40 if I had chosen two-day shipping) for a total of $35.25 for one iris!! Double yowza!! Call me cheap, but I can't convince myself to pay over $20 to ship one plant.

(Okay, now I'm thinking there is a different way of looking at this: Jack's birthday is in March, and I wouldn't think twice about spending $35.25 for a birthday present for him. Wouldn't this iris make a nice gift for his birthday? I could even chose the location and plant it for him . . . . Nah, he would never fall for that. To quote the potential First Gentleman, "that dog won't hunt.")

Perennials Getting an Early Start

Does it seem to you that when the flowers start popping, everything happens overnight? Here are some things in bloom in our garden today that I did not notice a few days ago. And it seems that most of these are making an appearance very early this year.

Wood Poppy 

Stylophorum diphyllum

Epimedium x versicolor 'Sulphrite'

Epimedium

Epimedium x rubrum

Coreopsis

Hardy orchid

Bletilla striata

Camellia japonica 'Pearl Maxwell'

Here's the one that concerns me with the cooler weather forecasted for the next few days. This camellia has blooms that remind me of the tissue paper flowers we use to make as kids (remember those?). The blooms both look like those tissue paper flowers and act like tissue paper when the temperature dips. Low temperatures won't damage the plant but can turn the blooms to mush. I bought a frost blanket especially for this camellia and I'll get it out for the 34-degree night forecasted for the weekend. Thiry-four degrees may not damage the bloom, but just in case. . . .

Don't be Fooled by the Pretty Blooms

The Bradford Pear (Pyrus Caleryana) is on the invasive plant list in many states, including Tennessee. If you have any doubt about its invasiveness, just pay attention in the next week or so to the abundance of trees with white blossoms you see everywhere. True, they can be lovely in full bloom, especially when planted along a driveway or parking lot like this:

But you may not realize that these trees are aggressively seeding themselves all over the area, crowding out native vegatation. Today I passed through Lakeland in the I-40 and Canada Road area. Along both the interstate highway and Canada Road, Bradfords are blooming everywhere: on slopes along the road, on entrance and exit right-of-ways, and in the woods and fields along the roads. I pulled off Canada Road to snap the picture below of an undeveloped area in Lakeland where "volunteer" seedlings have taken advantage of a fallow area to establish a forest of Bradford pear trees. (And I might mention that this was a very stinky place. If you've been downwind of a Bradford in full bloom, you know what I mean.) Unfortunately, I could have taken a similar picture at any of a dozen or more places along my route. 

So where did all these trees come from? Twenty-five years ago, Bradfords were a favorite in new housing developments because they are beautiful, fast-growing trees. It wasn't until the trees reached maturity that it became apparent that the weak, branching-trunk growth habit of these trees made them literally fall apart as they matured. The slightest wind (sometimes no wind at all) will cause huge sections of the trunk to split away, and they have an uncanny tendency to land on houses or cars or people.

Then, as new cultivars were developed to counter the weak branching problem of the Bradford ('Chanticleer', 'Aristocrat', and others), they cross-pollinated with the older varieties and became prolific re-seeders. Whether these new cultivars will correct the problem, remains to be seen.

So don't be fooled by the beauty of these trees. The fact that they are crowding out our native trees is not the only reason to avoid them. It's just the most noticeable reason at this time of year.

Spring Fling March 18-19

One of the biggest and best gardening events in the area is just around the corner. The Memphis Area Master Gardeners hold their Spring Fling in (and around) the Red Barn at the AgriCenter on Friday March 18 and Saturday March 19. Admission and parking are free.

There is a lot for a gardener to love about Spring Fling. For those of you who might not be familiar with this event, I would describe it as a learning and shopping extravaganza. Or maybe a learning/shopping/eating extravaganza, since I usually hit the Master Gardener food area first to pick up a cup of coffee and a homemade baked treat. (Be sure to check it out--Master Gardeners are wonderful cooks!) Spring Fling offers workshops and demonstrations, a variety of great speakers, and fun activities for children.

I usually time my attendance to coordinate with speakers I especially want to hear or demonstrations I want to attend. (You can view the schedule here.) Before and after these events, I shop. There are many garden-related vendors who set up booths offering everything from garden supplies to garden decor. One year, I bought this charming, gently-used garden lantern from a vendor. You never know what treasures you will come across.

And, of course, you can shop for plants. The Master Gardeners have a plant sale area, and many of the local nurseries have plant booths. It's a great time to pick up that plant you need, or if you are like me, that plant you didn't know you needed until you saw it at Spring Fling!

See you there next weekend!

Managing Foliage of Surprise Lillies

Spring is the time of year when our surprise lilies test my patience. If you have them, you know what I meant. They produce a massive amount of foliage that crowds out everything and then turns brown and flops over before dying back for the summer. (That is, if you can stand the foliage long enough to get to the flopping stage.) 

Similar to daffodils, this foliage must be allowed to grow in the spring so that the bulb will have enough energy to flower in late summer. The picture below from a previous summer shows the motivation for putting up with the unruly foliage. The flowers that appear, seemingly overnight, are really lovely, especially when they are massed.

Last summer Jack and I built a little dry stream bed to allow for drainage through this area. In building the stream bed, we damaged and otherwise destroyed some of the lily bulbs, and I wasn't certain how many we would have this spring. But, as it turns out, we still have a fairly large number. When the foliage appeared, Jack asked me if I was going to take the bulbs out (as I threaten to do ever year). But I really do enjoy the flowers so I've decided to try to find a way to put up with the foliage.

After we made the dry stream bed, we planted some hostas along the edge of it. It will be interesting to see how well these rather small hosta hold their own with the lillies. I know that they won't hide the lily foliage, but I'm hoping they will provide something more pleasant to look at when the lily foliage starts declining.  

Hopefully, the hosta will help, but they aren't a total solution. Just thinking aloud now . . . maybe I need to interplant something that would come up in the spring and bloom late spring to mid-summer? I have several purple coneflowers in that area and I usually have a lot of "volunteer" seedlings. What if I created a swath of coneflowers above the lily foliage? I wonder if I could manipulate the bloom of the coneflower by timing the cut-back so that I got a bloom flush both before and after the bloom of the lily? (Gardening experiments are so much fun and failure is rarely a big disaster!)

I'm sure other people have ways of dealing with surprise lily foliage, and I'd love to hear your ideas.