Great garden bulbs: Sternbergia lutea

Last year, I visited Montrose and became bewitched by a charming little bulb I’d never seen before: Sternbergia lutea.

A diminutive amaryllid native to the Mediterranean, Sternbergia lutea isn’t widely grown, but it should be. It looks like a tall yellow crocus, but blooms in September. The blooms can be short-lived, but they are followed by grassy green foliage that persists through the winter, then disappears as the rest of the garden wakes up in the spring.

Sternbergia lutea growing at Montrose.

Sternbergia lutea growing at Montrose.

They like their summers dry–so dry, in fact, that the bases of oak trees provide ideal planting conditions –and prefer being left alone. Heavy clay doesn’t bother them,  either. Don’t lime them, whatever you do, and keep them clear of automated watering systems.

I think they’d look spectacular mixed into a bed of black mondo grass, Ophiopogon planiscapus ‘Nigrescens,’ which will tolerate the drought-like conditions the Sternbergias need in the summer, or another dark-leaved ground cover like Ajuga reptans ‘Mahogany.’ Alternatively, a broad-leaved, yellow-variegated ground cover like Lamium maculatum ‘Anne Greenway,’ would complement the blossoms handsomely.

Lamium maculatum ‘Anne Greenway.’ Photo by GrowingColors.com.

Ophiopogon planiscapus ‘Nigrescens.’ Photo by RareFindNursery.com

Unusual garden bulbs make great garden plants. They’re easy for the novice gardener, cheap to buy and grow (many reseed or reproduce by offsets, and require little in the way of fertilizers or pest management schemes), and many bulbs can last forever in the home garden.  Brent and Becky’s Bulbs in Gloucester, VA, carries Sternbergia lutea, among other terrific and unusual plants. And they’re not a sponsor of my site; I just like them.

What are your favorite plants for the fall garden?

Controlling flea beetles in the fall garden (help wanted)

I didn’t get row cover on my beans in time this spring, and the flea beetles found me.

tired beans

Flea beetle is something of a catch-all term used to describe several species of beetles (not all of the same genera), all of which are tiny (1/16 to 1/10 of an inch long), that live in the soil and cause mayhem in North American gardens. They adore feeding on your vegetable plants, and can reduce a favorite crop to smithereens if not dealt with promptly. One treatment won’t suffice: They can produce four generations or so in a warm-climate growing season. Overwintering adults typically emerge when temperatures hit about 50 degrees (10 C). In recent years, it’s been 50 degrees at Christmas.

Here is my quandary: Their preferred cuisine is cruciferous, which happens to be what I need to get planted soon. Most winters are mild enough here that greens and root crops may be harvested year-round if grown under horticultural fabric, but that means getting seedlings and transplants off to a good start, starting now.

Row covers can be effectively employed to exclude flea beetles from pristine soil, but (clearly) that’s not what I have. Installing row cover where an infestation has already occurred just traps the beetles inside, keeping them safe from predators while they devour your spinach. Row cover must be sealed tightly all the way around to be effective, by the way.

Trap crops come highly recommended. “Plant a crop of mustard greens!” the gardening literature exhorts. Alas, the trap crops are what I want to eat this winter. Kale, collards, mustard greens, broccolini, radishes, tatsoi, arugula. These are the seed packets sitting on my desk, awaiting my decision. I fear that planting a trap crop, even far away (relatively speaking) from the vegetable bed, will only encourage more of the little punks to move in and feast upon everything in sight.

The garden literature also recommends scouting newly planted beds and counting the beetles as they arrive. This presumes the gardener can count insects best differentiated from dirt with a hand lens before they jump to the safety of the earth. Anyone who has brushed against a plant infested with flea beetles has seen a spray of tiny bugs fleeing the scene of the crime. Who can possibly count them in situ? Even if the gardener manages to hunker silently down and get a view of the action, must she hold her breath to avoid disturbing them? What if she needs to sneeze? (It’s fall pollen season, you know.)

Flea Beetle Management for Canola, Rapeseed, and Mustard in the Canadian Northern Great Plains. Graphic by the Government of Saskatchewan.

I don’t want to spray if I can avoid it. I have been known to pull out the neem oil from time to time, but it’s only moderately effective against flea beetles.

What to do, then?

Possible solutions to flea beetle infestation

I’m tempted to try one or a combination of the following. Have you had success with any of these?

1. Diatomaceous earth. DE is a fine powder made of fossilized remains of diatoms, a kind of algae. When used as an insecticide, the powder absorbs components of the waxy coating of insects’ exoskeletons and causes them to dehydrate. It’s critical to obtain food-grade DE for this application to be effective.

2. Interplanting with garlic. Garlic is a moderately effective insect repellant when sprayed on plant surfaces. I have to plant my garlic somewhere; I suppose it may as well go between my rows of kale.

3. Parasitic nematodes. To read about parasitic nematodes is to discover another of Mother Nature’s horror shows. Employing them can be a bit tricky, because the gardener must get the correct kinds of nematodes (families Steinernematidae and Heterorhabditidae, and some species are picky about who they infect); time the application to coincide with a larval stage of the target species; and keep the soil moist, not too hot, and not too cold.  On the plus side, they don’t infect birds or mammals.

Parasitic nematodes. Photo by Penn State University Extension.

Given my warm climate, and extrapolating unscientifically from the graphic above, I guess I might be able to interrupt a larval cycle if I went out tomorrow and applied the nematodes…maybe?

Please send your advice, post-haste.

Comfrey: A plant’s smelly, magical wonder food.

Using commercial fertilizers, particularly sustainable or non-synthetic ones, can get really expensive. Compost and manures add important organic matter to the soil, which helps to build the subterranean ecosystems that support plant health, but they don’t add much in the way of major nutrients.

Fortunately, nature has provided a means to make our own sustainable fertilizers. Comfrey (Symphytum officianale), a plant that grows well in most gardens, provides nutrient boosts when added to compost or used in liquid fertilizers. And once you’ve bought the plants, it’s free.

Comfrey plants (Symphytum officinale) photo by Trish Steel [CC-BY-SA-2.0 (http://creativecommons.org/licenses/by-sa/2.0)%5D, via Wikimedia Commons

Comfrey is a borage relative. Hardy to Zone 3, it has large, broad leaves like those of Pulmonarias, to which they are related, and small clusters of blue or white pendulous flowers. Comfrey’s fuzzy, sometimes prickly leaves discourage insect pests. It grows in a range of soils in sun to part shade, and uses its impressive root system, which may grow anywhere from 6 to 10 feet deep, to mine minerals from the subsoil, aerate its surrounding soil and break up the heaviest clays. It will regrow from tiny slivers of root, though, so be sure to plant it where you want it. If you are as indecisive as I am, grow it in a container. You won’t get quite the same level of benefits as compared to comfrey grown in the ground, but at least you won’t have it permanently installed.

Comfrey has been used in the past as an herbal medicine, but research proves comfrey contains poisonous chemicals called pyrrolizidine alkaloids (PAs). The roots contain up to 10 times the amount of PAs than the leaves. Its toxic chemicals can be absorbed through the skin, though, so it is advisable to wear gloves when handling comfrey. Do not take comfrey internally, as it is extremely toxic to the liver and may also be carcinogenic.

Comfrey (at right, with large leaves) and stinging nettle (Urtica dioica, at left, with serrated leaves) grow together in a barrel in my garden.

Comfrey (at right, with large leaves) and stinging nettle (Urtica dioica, at left, with serrated leaves) grow together in a barrel in my garden.

For plants, though, it’s a wonder food.

Comfrey contains high levels of the macronutrients nitrogen (N), phosphorus (P), and potassium (K), as well as calcium and vitamin B12.  Comfrey also contains allantoin, a chemical compound that stimulates cell growth and regeneration. It may be the allantoin that makes comfrey so effective as a fertilizer. Extracts from comfrey’s leaves have antifungal properties, and have been shown to effectively combat powdery mildew.

It’s good to know the specific epithet of the plant you’re getting. Symphytum officianale, the species, will seed prolifically and may become problematic in the home garden. The Bocking 14 strain of comfrey (Symphytum x uplandicum) contains the high nutrient levels of the species, but it’s also sterile, so it won’t self-seed and become invasive. Bocking 14 is difficult to track down in the United States, but is available from a few Internet sources.

Comfrey leaves can be used as a mulch or buried in the garden bed at planting time. As they rot down, they’ll enrich the soil. Take care when using them as a mulch, though: The decaying leaves can be attractive to slugs, so don’t mulch with them around leafy greens or ornamentals like hostas.

A more versatile way to use comfrey is as a liquid fertilizer or tea. To make the tea:

  1. Chop up a handful of fresh leaves (use gloves), and place in a container with a well-fitting lid.
  2. Add water to cover, submerging the leaves with a rock if necessary.
  3. Let the mix rot down for 3-4 weeks. At this time, the comfrey will have been reduced to a stinky black goo.
  4. Dilute the comfrey liquid concentrate at a rate of approximately 1 part comfrey to 15 parts water. The final product should be light brown in color, like weak tea. Water it in around your plants that need a boost, particularly fruiting plants, or use the tea as a foliar spray on plants that are susceptible to mildew.
  5. You can seal up the rest of the concentrate for use at a later time, or bury it in the compost pile to supercharge your compost.

Comfrey tea is higher in phosphorus and potassium, so you may wish to blend it with nettle tea to get a better nitrogen boost. This tea will feed the soil as well as your plants, ultimately making your plants more resilient. For a gentle, natural fertilizer, comfrey is hard to beat.

Introducing my not-so-itsy-bitsy garden spider: Argiope aurantia

The other morning, I noticed a large spider in a yucca plant near the road in my blue slope garden. Yesterday afternoon, I nipped out to see if it was still there.

The black and yellow argiope (Argiope aurantia)

The black and yellow argiope (Argiope aurantia)

The black-and-yellow argiope (Argiope aurantia) is fairly common throughout the US and Canada. It lives in shrubs and tall plants in meadows and gardens, and eats the small flying insects it catches in its web, which may be up to 2 feet in diameter.

This is a female spider. Like most of her species, she spends her time hanging head-down in the middle of her web. I haven’t yet found an egg sac, but I shall keep looking. It will be a half-inch to an inch in size, coated in a brown papery covering, looking a bit like a fat acorn. The eggs hatch in autumn, but the young overwinter in the sac and disperse in the spring.

argiope close 2

The zigzag pattern in the web is known as a stabilimentum, but its purpose is of some debate. These spiders eat and rebuild their webs every day, except during periods of molting and egg-laying.

I watched her for perhaps five minutes, during which time she seemed to feel peckish. She turned around and began climbing towards the bundle she’d wound up earlier.

argiope climbing 3

 

argiope climbing 5

The short, light-brown leggy structures with which she seems to be holding the prey are called pedipalps. Although they look like legs, they function more as antennae. She uses her pedipalps just as it appears, to hold the prey steady and guide it to her mouth.

She wrapped herself around it, perhaps taking a sip in the process, and then moved her dish to another spot on her web.

argiope climbing 7

argiope climbing 8

argiope climbing 9

argiope dinner time

argiope my dinner argiope moving food argiope taking food

Wildflower Wednesday: Joe Pye Weed

My garden doesn’t have many fall native wildflowers (yet). One I do like very much, though, is hollow Joe Pye weed (Eutrochium fistulosum).

Hollow joe pye weed

Native to eastern North America, Eutrochium fistulosum forms a massive clump, growing 5-8 feet tall and 4 feet wide in the moist soils it likes. Mine is a bit on the drier side, and so grows correspondingly shorter, topping out at around 6 feet high and 3 feet wide. During rainy spells in summer, I can practically watch it grow. 

Butterflies and bees love the flowers, which are rich in nectar. 

My plant suffered a setback from last year’s weather, I think; it’s half the size it was last year. Or perhaps it’s time to dig and divide. I’m keen to keep it going because it attracts so much wildlife. And the seed heads look beautiful all winter, especially under ice.

Ice on Joe Pye weed, Eutrochium purpureum

Ice on Joe Pye weed, Eutrochium fistulosum

Season: midsummer through fall; winter interest
Height: 5-8 ft.
Flower Color: Rosy purple.
Hardiness: USDA Hardiness Zone 4-8
Foliage: Lime green, lightly serrated. Red stems.
Flower: Loose, rosy purple inflorescences.

Site: Prefers moist sites but will cope with average to dry soils.

Propagation: Division spring or fall.

Exposure: Full sun to partial shade
Soil: Moist and well-drained to wet. 
Origin: Eastern North America
Life Cycle: Perennial

Wildflower Wednesday is a celebration of wildflowers from all over the world. It’s hosted by Gail and Clay and Limestone on the fourth Wednesday of each month.