It’s about to begin. In a couple of weeks here in southern New England, (late November), we’ll start to notice clouds of dull gray brown moths fluttering about at night, attracted to the glow of porch and street lights. Mating season for the Winter Moth, Operophtera brumata, is about to begin as both male and female moths emerge from their pupae. They will procreate into December, or as long as mild enough temperatures prevail.
In our recent research for the best methods to combat this destructive pest (Winter Moth caterpillars devour new plant growth on many of our most highly desirable ornamental trees and shrubs), we came across great news! University of Massachusetts Entomologist Joe Elkinton and his team have solid evidence that a parasitic fly, Cyzenis albicans, is an impressive natural control for Winter Moth. At four test sites where the parasite has been released throughout southeastern MA (Seekonk, Hingham, Falmouth and Wellesley) populations of winter moth have dramatically decreased. Here is a link to an article.
Isn’t that fantastic to read? However, while we are waiting for this helpful parasitic fly to move into our neighborhoods, we must begin preventive measures. It is necessary to understand the Winter Moth lifescycle to plan and time your defense. The first meaure is to apply sticky tree bands around treasured specimens, which trap the females as they adhere and climb up tree trunks, emitting their sex pheromone to attract the males. After the mating scene has occurred, female moths continue to climb to the top of trees and shrubs and then lay their eggs in the bark and crevices near branches. Adult moths die at this stage.
Other types of botanical controls can be applied over the winter and early spring. In late winter, dormant oil spray can be applied to branches to suffocate the eggs. In early spring, Bacillus thuringiensis a.k.a. BT, a beneficial bacteria, can be used to effectively control the caterpillars as they emerge from their egg sacs and seek nourishment from the young unfurling foliage. Spinosad is another bio insecticide, and is available to homes owner under product labels Monterey Garden Insect Spray and to licensed pesticide applicators as the product Conserve. Care should be taken to avoid applying Spinosad when bees are active.
I’ll confess. I had avoided repotting (for almost a year now) what had become one very sad looking Agave. The older leaves had become brown and ugly, and obnoxious weeds had taken root. The piercing tips and teeth on the leaves looked ferocious, and I didn’t want to give blood. So there it sat, in a neglected corner, a woeful sight indeed.
As we were gathering all the tender plants to bring inside for the winter, it was time to make a choice about whether to save or toss the misbegotten Agave. A decision was made: yes, save it. A plant that has the will to carry on despite such neglect deserves not only respect; it deserves admiration. And as it turned out, grooming and repotting wasn’t a big deal after all. Here’s how we went about it:
The first thing to do is put on some protective gloves. Carefully remove the Agave from its pot, standing over a wheelbarrow or large receptacle to catch the debris. Tilt the plant so you can get at the base of the crown with your clippers and remove the dried up foliage. Next, loosen up the soil around the roots and remove any weeds that may have established, teasing out their roots so they won’t make a comeback.
Use a very well drained soil mix amended with sand and perlite, and if you have access to grit or gravel, add some too. (We don’t add fertilizer, since Agave are very light feeders. Instead, we liquid feed with fish emuslion/seaweed 2 or 3 times a year.) Position the Agave in the center of the pot, and then backfill. The repotting is accomplished, and we can now place the Agave in a spot where it merits attention.
We’ve been asked recently if we had ever written a post on wintering over tender plants in cold climates. The answer is yes, we have, in the fall of 2010, but it certainly would be convenient if we posted easy access links to the 3 articles for those who may have missed the postings or for those who want a quick refesher.
Thanksgiving is a bit early this year, which is good and bad. Good, because we can enjoy this autumnal feast among family and friends without paying heed to retailers’ nagging “there’s only 4 weeks left before Christmas”. Bad, because, if you’re like us, there are still more tasks and cleanup to do outside, and we gave ourselves a tentative deadline for wrapping up the “putting the garden to bed” chores –Thanksgiving.
Fact is I don’t think there’s ever been a year when we’ve completely “finished” this end of the season chore. There’s always so much to do. A prioritizing list helps us focus on the most important tasks, but we always have so many good intentions. If the weather holds out longer, we’ll take advantage of whatever reasonable days we get to plant the rest of the bulbs or to tackle dividing and transplanting the Siberian Iris that haven’t bloomed well for 3 years.
And what if the garden itself doesn’t want to be “finished”? Our raised vegetable beds are still producing lettuce, kale, carrots, parsnips and beets. We’ve mulched our beds with rinsed and dried seaweed, which protects and insulates the soil for easy digging. To extend the season as long as possible, this spring Chris purchased a hoop bender from Johnny’s Selected Seeds which enables us to make inexpensive supports from galvanized electrical conduit for covering planting beds. The installed hoop frames can be covered with Remay or clear plastic to rebuke the hard frosts. These hoops just might enable us to harvest lettuce into the New Year!
The most frequently asked question regarding seed collecting is “How do I know if seed is ripe?” Here’s a very general answer, for seeds of different plants ripen at different times, and their appearance, when ripe, can be as different as the individual plants that produced them. You need to keep a watchful eye. Observe the green immature pods over time, and suddenly you’ll notice brown seed capsules ready to split and burst. If you are not vigilant, you may discover empty seed pods days later, and your opportunity will have passed. (You can also try placing a paper bag over the immature seed capsule, securing it with string. When the seed ripens it will be contained in the bag.)
Collecting Tips: Mature seeds are usually dark in color, firm, and dry. Seeds that are green and moist are usually immature and generally will not germinate or will produce unhealthy seedlings. The flesh of pulpy fruits often becomes soft and changes from green/yellow, to red or blue-purple when ripe.
Cleaning: In a cool dry space, place dry seed capsules in a paper bag, secure with string and hang upside down. Clustered seeds of composite plants such as Asters and Marigolds might benefit from being laid out on newspaper layers and allowed to dry more completely. Remove the chaff and other vegetable matter which may harbor fungal spores which will spread and infect the seeds. Moist seed from fleshy fruit such as tomatoes, or from ornamentals such as Arisaema, should have the mucilage (the wet medium surrounding seed) rinsed off. Place the ripened seed in a sieve and rinse off thoroughly. Spread rinsed seed on layers of newspaper and allow to air dry.
Storage: Only store cleaned and dry seed. The combination of moisture and warmth will cause spoilage. Store seed in paper envelopes or bags to allow them to breathe. Don’t use plastic baggies, which may trap moisture. Keep your seeds in a cool dark dry space. Your refrigerator would work, if you have room, or perhaps a closet or cabinet in a cool room. Clearly label all packets with all pertinent information.
Important: Remember the lower the humidity and temperature in storage, the longer the viability of the stored seed
For more info online: http://theseedsite.co.uk/harvesting.html If you really want the specifics, you need the seed germinating bible. Norman Deno’s book Seed Germination, Theory and Practice can be purchased through the North American Rock Garden Society’s Bookstore.
This article is appearing before most of us have had a killing frost, but take a moment to read this now so you’ll have an idea of what to do when the time comes. The processes described below are general and reliable instructions, but we’ve had luck simply wintering over dormant plants in the containers they were grown in, stored in the same cool, dark but above 35f temperatures.
WAIT UNTIL AFTER there has been a killing frost, when the foliage has blackened and in some cases toppled over (you want to be sure active growth is halted). Then it is time to gently unearth the corms, tuberous roots and rhizomes of tender perennials such as Canna, Colocasia, Oxalis, Gladiolus, Dahlia, Salvia guaranitica, Mirabilis, Phygelius and others. Be careful, as cuts and breakage of fleshy tubers invite disease and decay. (If pieces of root become broken or cut, remove the affected divisions or treat with a garden fungicide to prevent fungal diseases from developing and spreading.) It is always a wise practice to sterilize shovels and forks after digging each clump, so as not to spread disease. Remember to write on a tag each variety of plant as they are dug, and attach. It is so easy to mix up root stocks, especially if you’re growing more than one selection of a certain plant.
The next thing you should do is clean and cure your roots. Wash off with a hose sprayer as much of the clinging soil as possible, which will rid you of possible pests and pathogens lingering in the soil. You may want to dip the clean roots in a fungicide solution at this point as a preventative action. (We may try the botanical all purpose Neem this year, which has fungicidal properties as well as insecticidal.) Lay the roots to cure or dry in a protected well ventilated area out of direct sunlight. This may take a few days or up to a week or two, depending on the plants, weather and temperature conditions.
In the meantime locate some ventilated containers to store the roots, such as wooden crates or apple baskets. Plastic covered bins are easy to acquire, but be sure to puncture holes in the sides for ventilation. Be sure to include a label in each bin. First put down an insulating layer of clean wood shavings, almost dry peat moss, a well drained barky soil mix that that is just a tad moist, or even sand, and lay down the roots, covering each layer with an inch of your medium, being careful to not to let the roots touch. Place the bins in a dark cool area that stays above freezing. A cool, slightly humid root cellar would be perfect, and if you live in an ancient house like we do, your cellar may be the perfect spot. Any basement, shed or garage that is dimly lit and cool will be fine, as long as it stays above freezing. You may want to check the bins occasionally to monitor if mold is beginning to develop. If you do catch fungal problems, immediately discard the affected roots and remove what’s left that look healthy. Treat the healthy roots with a fungicide, (acts as a preventative) and place in a clean bin with fresh shavings, soil mix or sand.
Suddenly, one morning you wake up, and the chill in the air alerts you that autumn has unofficially arrived. Once the nighttime temperatures begin to dip into the 40’s, it’s time to start bringing plants indoors, beginning with those that are only hardy to the warmer zones 9, 10 and 11. (Think Alpinia, Coleus, Cuphea, Acalypha, Alternanthera, Cyperus, Impatiens, etc.) If available space is a concern, be selective and choose the hardest to acquire specimens first. Do you have a warm space available that is well lit and humid enough for tropicals, such as a bathroom or laundry room? Remember that indoor heating systems create a warm but dry air environment. Plants that prefer more arid conditions, such as tender succulents, Pelargonium, and some Begonia easily adapt to the transition indoors.
Important! Here are two things you should do first. The days are getting shorter and there is less light available indoors. Plants will begin to respond to the change in temperature and light by dropping foliage, and in some cases flower production ceases. To counter the low light levels, we recommend trimming back large leafy plants so there is less growth for the plants to support. Also, inspect plants for insect activity and as well as burrowing snails, slugs and other hitchhikers. Spray with a botanical pest control, such as insecticidal soap or Neem. Spray again in 7-10 days to arrest any late hatching, and monitor in the weeks to come.
Plants that are hardy to zones 7 and 8 can handle cool winter temperatures in the 35-40 degree F. range, and will do well in a sunny attic, basement or garage. These plants include Abutilon, Phormium, Fuchsia, Phygelius, Hebe, Coprosma, Astelia, Centaurea,many Salvia and Pelargonium, to name a few. Remember that since their growth has slowed down due to lower light levels, stop fertilizing and water just enough to keep them from drying out, as constantly wet soil contributes to root rot.
Next week’s article: Storing dormant roots.
You’ve acquired a collection of stunning tender perennials that have added so much to your containers and gardens, but soon, frost will be imminent. Before you drag dozens (hundreds?) of pots indoors, first consider how much storage room your home/garage/cellar offers, (let’s assume you don’t have a greenhouse, but if you do, terrific!). Usually space is quite limited, and you’ll need to be ruthless in deciding what gets saved. Focus on the hard to find varieties. Next, decide what needs to be actively growing, and what can be stored as dormant roots (more on that in later blog postings). In general, plants that are the least cold tolerant (zones 9, 10 and 11), i.e. Coleus, need to be kept in an active state and need warm indoor temperatures.
We found that taking cuttings of easy to root plants like Coleus, Salvia and Cuphea is one way to limit the number of big bushy plants that will compete for light on your windowsill. Begin taking cuttings at the beginning of September and be sure to label each variety. Select non flowering tips with 2-3 nodes and remove the lower leaves. Dip the tips in a light rooting hormone and stick in a tray or pot of a light potting medium or sand. Place in a shady warm spot and water/mist several times a day for the next 2 weeks or so. A gentle tug will let you know when roots have taken hold. Once decent roots are set, gently unearth and transplant into small pots, or leave in the rooting pot itself. Go light on the fertilizing this fall and winter, since you do not want to encourage too much growth. In the spring, transplant into a richer soil mix. You can begin taking more cuttings as soon as vigorous fresh growth permits.