Late Summer Round-up

Wildflower border in early September.

As summer is winding down for us, it is still going strong for the summer and fall-blooming wildflowers.  In this border on the south side of the house the flowers are sharing space with a few varieties of tomatoes.  Notable here is the Brown-eyed Susan, Rudbeckia triloba.  This plant is also growing in part sun, in dryish soils (I have some doing well near a Norway Maple, but it gets 3-4 hours of sun), but fades out early in deep shade.  Also in this border is the annual Crowned Beggarticks, Bidens coronata.  These are of a more manageable size, and bloom earlier, than the Bearded Beggarticks, B. aristosa, that I have grown in the past.


One plant that is expanding its presence in the border is Texas Sage, Salvia coccinea.  This southeastern native annual has managed to overwinter in the warmer locations here in my northeastern garden and in the pots where I have reused the soil.  The original planting was done 3 years ago, but that doesn't mean that a really cold winter will finish them off.

The bees access the nectar at the base of the flower

The Smooth Asters, Symphiotrichum laeve, have been blooming for about a week.  I don't usually see them blooming with the Black-eyed Susan's, since they usually get dried out here in late August.  I started out with only a couple of these asters, but now they a showing up all around the garden.  Another plant that has adapted well to this residential site is Wild Petunia, Ruellia humilis.  The tiny seeds of these plants are finding their way into pavement cracks and then growing with some success.  They bloom all summer.  I didn't take a photo because they are looking kind of ratty now as they are going to seed.


One new plant I started this year was Giant Blue Hyssop, Agastache foeniculum.  The natural range for this mid-west native does not extend to Massachusetts.  The indigenous Agastache is the Purple Giant Hyssop, A. scrophulariifolia, and it grows to over 6' tall.  Since I wanted to grow this in a small residential setting I opted for the smaller sized species.  I was happy to see that, despite its youth, it has started to bloom.

This new Agastache is attacting bees already;
however, the nearby Beeblossum gets little traffic.

I have been growing Meadowsweet, Spiraea latifolia (actually Spiraea alba var. latifolia) around the house for over 5 years.  It is long blooming and very attractive to the native bees.  The down side is that it gets very rangy and tends to flop over onto other plantings.  This year, after the first big flush of flowers was spent at the end of June, I pruned a plant back by about half.  Now in September it is blooming again and has a more contained shape.

Probably the best place for this plant is in a hedgerow or a naturalistic planting; however, with some attentive maintenance it can work in an informal residential design.

Update: Native Seeds for 2011

Following up on the Native Seeds for 2011 post, here’s a status report on what has and has not worked so far…

Did not germinate:

Allegheny vine (Adlumia fungosa) I’ve written a lot about this biennial vine. I just can’t get enough of it. I was surprised that the new seeds I bought this year did not germinate; however, I do have one self sown plant that is doing great and should be blooming soon. I also have overwintered and planted out some from last year. I’ll need to make a point of harvesting my own seeds this year.

Fern-leaf False Foxglove (Aureolaria peduculata) This biennial is parasitic on oaks, but, reportedly, does not need them for germination. None of these have germinated, despite trying several different germination conditions. 


Butterfly Weed (Asclepias tuberosa) This is the first year I’ve tried these and alas, none had germinated. Fortunately I did get some bare root plants from Prairie Moon Nursery, and these are developing nicely.


Rosey Sedge (Carex rosea) I’ve had a small clump of this perennial grass for nearly 5 years. I was not able to get the seeds I bought this year to germinate. I understand that Carex is generally a difficult plant to grow from seed.


Good germination:

Pearly Everlasting (Anaphalis margaritacea) This is a perennial with white, long lasting flowers similar to the annual Sweet Everlasting (Pseudognaphalium obtussifolium) that I’ve tried several times before. These germinated really well, but have grown on very slowly and so far have not transplanted well. I just may not have the right touch, or location, for these plants.

Tall Swamp Marigold or Crowned Beggarticks (Bidens coronata) is an annual, with good-sized yellow flowers. These did not germinate last year when I cold stratified them in moist sand for 60 days, so this year I got a new batch of seed and conditioned them in moist soil for 60 days in the refrigerator. I was thrilled to see that they were sprouting within 5 days of coming to room temperature. I’ve got these blooming in the garden already! So far I would rate these better than the Bidens aristosa, for early bloom and a manageable size; however it’s still early so we’ll see how long the bloom continues and how vigorously they reseed themselves (a little, a lot or none at all?).


Browneyed Susan and American Pennyroyal in a pot.



Brown-eyed Susan (Rudbeckia triloba) is a short-lived perennial, that while taller has a more delicate appearance than the typical Black-eyed Susan (R. hirta). Last year when I conditioned these in damp sand I got no germination. This year moist stratification in the soilless mix resulted in good and rapid germination after just 4 days of coming out of the refrigerator. I’ve moved some of these to pots and some into the garden. I don’t know if these will grow on to bloom this year, or if they need a season to get established.






Some germination:

Flowering Spurge (Euphorbia corollata) Perennial also known as Wild Baby’s Breath. I thought this could be good for general landscape use, with white flowers through mid-summer. I got a low rate of germination and the plants seem slow to develop. Once the temperatures got over 90, the seedlings began to take off. I’m trying this in several locations and have this one in a pot. So I’m hopeful that at least one of these will mature.

Woodland Sunflower (Helianthus divaricatus) Perennial for dry shade. This plant can be weedy in the garden, but I really want to test it out under the Norway Maple where its vigor may be tempered by this challenging environment. Only 4 of these germinated, but these are developing nicely. I’ve already moved a couple under the 'nasty' Maple and they are continuing to grow.



Repeats, with good results:

Orange Hummingbird Mint (Agastache aurantica ‘Navaho Sunset’) grew quite well last year and I got good germination from the same crop of seeds as last year. Last year’s plants are a dense mass about 18” tall, not ready to bloom yet, but the foliage smells really great, even as tiny plants.

Native to rocky slopes, these transplants
are doing well among some Bearded Iris.

Rock Harlequin (Corydalis sempervirens) Even though the seed was for 2010, still gave a very good rate of germination. Some seedlings that I transplanted into rich humusy soil died immediately, while those interplanted with the Bearded Iris, in unimproved soil, are doing quite well.
















Sulfur Cosmos (Cosmos sulphureus) these germinated well both indoors under lights and direct sown in the garden. I was concerned that I would confuse the seedlings with those from the Bidens aristosa that has reseeded itself all over the garden beds. There are a couple of features that distinguish the seedlings. The first pair of leaflets from the Cosmos are each nearly an inch long, compared to about ¼” for the Bidens, the Cosmos germinate about 2 weeks later than the Bidens (although the Bidens continue to germinate from late April to the middle of June) and while the leaves of both species are deeply divided, the Cosmos have broader rounder tips than those of the Bidens. I am pulling up and discarding the Bidens seedlings, this will be a test of whether I can eliminate this species from the garden so that I can test other plants.



Note the long cotyledon leaves and rounded leaf tips

 

Compare the first pair of leaves with
those of the Cosmos.

















The annual American Pennyroyal (Hedeoma pulegioides) has been getting established from a planting 2 years ago. I’ve found that these reseed themselves rather well and grow well under lights (after 30 days cold stratification), but did not come up where I seeded them directly in the garden. I guess these do better when they find their own home. I’ve planted out a few of these and am growing some in pots. I plan to snag a few leaves to rub on my arms to test their mosquito repellent properties.


Spotted Beebalm (Monarda punctata) had germinated within 6 weeks in damp sand, while still in the dark in the refrigerator. I moved the germinated seedlings to starter mix and still ended up with a healthy crop of little plants.


Sweet Everlasting (Pseudognaphalium obtusifolium) has given me trouble on transplanting in the past two years. An this year is no exception – lots of seedlings that do not transplant well. The directly sown seeds did not germinate. I think need to be put into really well drained coarse soil and are not appropriate to my garden conditions.



This seedling is developing faster than ones transplanted from
indoors.  Monarda and Agastache are also cropping up.


Some other seedlings that are showing up on there own in the garden are from the Scarlet Sage (Salvia coccinea), Biennial Gaura (Gaura biennis), Strawberry Blite (Chenopodium capitatum) and of course the Swamp Marigold (Bidens aristosa). I was not certain if the seeds of the Salvia could overwinter here in the Northeast.  Seeing these appear in new locations points out the importance of knowing what the seedlings for these annuals and biennials look like, otherwise I would have weeded them out as I was preparing the beds for other plants.




The reseeded catnip has deeper teeth on the leaf margin than for the Salvia coccinea,
the catnip leaf is also has a fleshier texture.