Spring Bulbs Begin In Autumn

Spring bulbs bloom months from now.

Spring bulbs lack immediate gratification. They will, of course, justify their habitation of the garden as they bloom next spring. For now, they are not much to look at, and do not stay visible for long. While dormant, they poses neither foliage nor significant roots. Most look something like small and disfigured onions. Burial in shallow graves conceals their uninteresting exteriors through winter.

Cool season bedding plants can effectively obscure the otherwise bare soil over the grave sites of some types of bulbs. Mulch might be best for those that should start to grow immediately or that will develop an abundance of foliage. While plants above them may need watering until the rainy season begins, dormant spring bulbs need no more attention. They disperse roots through winter.

Spring bulbs, including corms, rhizomes, tubers and tuberous roots, are oblivious to the discomforts of transplant while dormant. However, they want to wake from their dormancy in situations that are conducive to normal development and bloom. Some prefer shallow planting. Others require significant depth for stability. Most but not all spring bulbs perform best in small groups or colonies.

Narcissus, daffodil and crocus are the first spring bulbs to bloom as winter ends, or even earlier. Tulip, hyacinth, grape hyacinth, freesia, anemone, ranunculus and some types of iris bloom shortly afterward. Late iris, lily and montbretia bloom later, and some types are considered to be summer bulbs. Spring bulbs become available in nurseries while seasonable. Summer bulbs arrive later.

Most spring bulbs bloom only once. Plaiting them in phases a few weeks apart within their respective seasons can prolong bloom. Each subsequent phase begins bloom as the preceding phase finishes. However, narcissus, daffodil, grape hyacinth and others that can naturalize will bloom simultaneously after their first season. Most spring bulbs unfortunately do not naturalize reliably here.

Gladiolus and allium are summer bulbs that bloom once. Calla, canna and dahlia bloom through summer.

Fertilizer Is A Seasonal Commodity

Fertilizer is about to be passe.

Fertilizer, in simple terms, helps plants grow. It provides a bit more of what growing plants crave. In some situations, it compensates for nutrient deficiencies. Fertilizer can be organic or synthetic. Various formulations serve a variety of purposes. Custom formulations appeal to plants with discriminating taste, such as citrus, orchids and roses. Slow release fertilizer lasts for a month or two.

Of course, proper scheduling of the application of fertilizer is very important. Fertilizer can actually become toxic with excessively frequent application. Fertilizer that provides significant nitrogen to promote vegetative growth after bloom can inhibit floral growth prior to bloom. Fertilizer that promotes root growth for new plants is unnecessary for mature plants. The diets of plants are variable.

Summer lingers later here. Regardless of the weather, it is now autumn. This is when deciduous plants start the process of defoliation for their winter dormancy. Evergreen plants are less obvious about their winter dormancy. Some remain active and even bloom through autumn and winter locally. Nonetheless, cooling weather and shortening days inhibit vascular activity of almost all plants.

Except for cool season vegetables and bedding plants, not many plants benefit from fertilizer applied this late. New plants might appreciate a bit just to help them adjust to their new environment. Some deciduous plants, particularly roses, like a last late application of fertilizer as they get ready for their long winter dormancy. Lawns might want fertilizer this late or perhaps later to stay green.

Otherwise, it is getting late to utilize fertilizer.

Late application of fertilizer can be very detrimental to plants that are sensitive to cool weather. Such plants typically finish growing through summer. By autumn, their mature foliage and stems are either resilient to minor frost, or are dieing back (defoliating) for winter dormancy. Fertilizer can stimulate premature development of new growth that will be much more sensitive to even mild frost.

Bare Plants With Bare Roots

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Dormant plants do not miss soil.

Knowing how colorfully bulbs will eventually bloom can initially make planting them disappointing, since there is nothing to see for all the effort. Planting bare root plants is not much more rewarding. The bare stems are a bit more proof of the effort, but will do nothing until they break dormancy in spring. Now that Christmas trees have vacated nurseries, bare root plants will be arriving, and will need to be planted before winter ends.

As the name implies, bare root plants have bare roots, without the soil they were grown in. Better equipped nurseries ‘heel in’ bare root plants in moist sand, which simply means that the roots get buried temporarily. When purchased, the plants get pulled from the sand and wrapped for the trip to their new home garden, where they get planted permanently into real soil.

Alternatively, bare root plants can be prepackaged in bags of moist sawdust. They only need to be removed from their packaging and sawdust before getting planted into the garden. Mail order plants, including plants purchased online, often get packaged even more simply, with a damp bag around the roots, maybe with a bit of gel or damp paper. The plants are safely dormant, so are not even aware of what is going on.

The main advantage of bare root plants is that they cost about a third of what typical nursery stock in heavier cans of media (soil) cost. Because they are so much less cumbersome, several bare root plants can be purchased at a time, and brought home in a small car without much effort. Since they lack the luxury of the soil they were grown in, they immediately disperse their roots directly into the surrounding soil.

Roots of bare root plants should be spread away from each other at planting. Soil amendment is nice, but should not be so copious that roots will not want to disperse outside of the amended soil. Even if rain is expected, newly planted bare root plants should initially get soaked so that soil settles around the roots. Grafted plants should be planted with the graft union above grade.

Fruit trees such as apricot, cherry, plum, prune, peach, nectarine, almond, apple and pear, as well as roses, are the most popular of bare root plants. Flowering crabapple, flowering cherry, poplar, willow, lilac, forsythia, wisteria and grape are also available.

Winter Is For Dormant Pruning

P90316++++The internet makes it possible to communicate with people who enjoy gardening all over the World. It can be amusing to hear what garden enthusiasts in Australia are doing now in early summer. Is it always summer in Ecuador? A common theme in much of America is that there is not much gardening to do right now. It might be more accurate to say that no one wants to go out in the cold.

Where winter weather is too unpleasantly cold to work in the garden, many winter chores can either be done earlier in late autumn, or delayed until early spring. Such scheduling is not a problem, since the plants involved are so deeply dormant through such cold weather anyway. Until the weather warms a bit, they do not want to work in their gardens either. Scheduling is very different here.

Not only does mild weather facilitate gardening chores, but it necessitates the completion of certain chores before the end of winter. Many plants that are mostly dormant while the weather is cool are actually dispersing their roots now that the soil is moistened by winter rain. They will be ready to break dormancy weeks before they would where winters are colder. There is no time for delay.

With a few exceptions, winter is the season for pruning here. Maples and birches should have been pruned earlier, or should be pruned later, so that they do not bleed sap. Citrus get pruned and groomed after the last frost because pruning stimulates new growth that is sensitive to frost. Early blooming flowering crabapples, flowering cherries and forsythias should get pruned after bloom.

Otherwise, most deciduous plants and many evergreen plants should be pruned in winter, while they are as dormant as they get. Pruning now will be less disruptive than it would be while they are more active. They wake up in spring and resume growth as if nothing happened, but relieved of the superfluous growth that was pruned away. Winter pruning is what fits best into their schedules.

Of all plants in the garden, deciduous fruit trees and roses rely on specialized pruning more than most others.

Spring Bulbs Get Planted Now

91023thumbTo those who do not enjoy gardening, the process of planting dormant bulbs must seem to be blatantly unproductive. Those of us who know what we are doing are so dutiful to select the bulbs we want, only to bury them in shallow graves in the garden, with nothing to show for all the effort. Knowing that the bulbs are buried at specific depths and orientations makes them no more exciting.

Only cool season annuals that might get overplanted after the bulbs get tucked in will provide any degree of color between now and when the freshly planted bulbs bloom early next spring. Light mulch might be added in conjunction with the overplanted annuals. Thicker mulch can be added without overplanted annuals. Otherwise, there is no immediate gratification with bulbs planted now.

We plant them because we know what they will do next spring. After their boring dormancy, spring bulbs will provide the most spectacular blooms in the garden as winter becomes spring. As they finish, summer bulbs that we might plant a bit later will continue through summer, with the latest continuing into about this time next year. There are no annual bedding plants that do what bulbs do.

Dormant bulbs become available in nurseries when it is time to plant them. Right now, it is time for the early spring bulbs like daffodil, narcissus, tulip, hyacinth, grape hyacinth, freesia, anemone, ranunculus, montbretia, crocosmia, crocus, most lily and some types of iris. We should get them into the garden soon so that they can slowly disperse their roots through the cool and rainy winter.

Summer bulbs such as gladiola, dahlia, allium, calla and canna, will become available later because they should probably be planted later. Although some might not mind getting planted early, a few, such as dahlia and canna, would likely be damaged by frost if they started to grow too early. Many of the summer bulbs bloom through a long season, rather than just once for a brief season.

Bulbs and bulb-like plants that bloom only once can be planted in phases every week or two through their season in order to prolong bloom.

Fertilize For The Last Time

91009thumbFor many of us, this might seem to be irrelevant. We do not apply fertilizer to our landscapes and gardens. Some of us who use fertilizer do so mostly for seasonal vegetable plants and flowering annuals. Such plants will either not be around long enough to get fertilized again this year, or are cool season plants that are on a completely different fertilizer schedule through autumn and winter.

Two other main exceptions that that might continue to get fertilizer after summer are lawns and houseplants. Some types of turf grasses, particularly those in older lawns, can get a bit pale through the the cooler parts of winter, so appreciate a boost. Houseplants are mostly immune to the cold weather outside, so continue to to crave nutrients, even if slowed somewhat by shorter day length.

So, except for lawns, houseplants, and incoming and outgoing annuals and vegetables, most other plants in the garden do not need to be fertilized again until weather begins to warm next spring. Not only do they not need fertilizer, but some could be inconvenienced by it. They know what time it is, and that they should now be slowing down for winter. Fertilizer can interfere with the process.

There are a few reasons why plants slow down or go dormant through winter. Some of the nutrients that they need to maintain active growth are less soluble or otherwise less available to them at cooler temperatures. There is less sunlight too. Plants from climates with cooler winters tend to be more proficient with winter dormancy. Many are deciduous to limit damage from wintry weather.

Some plants might use a late application of fertilizer to get ready for winter dormancy. Others might just ignore it as it leaches through the soil. Those that are from milder climates might try to use it to continue growing later than they should. For plants that are potentially sensitive to frost, growth that develops too late will not likely mature soon enough to be resilient to even mild winter frost.

This is why fertilizer can be applied to many plants one last time about now, but no later.

Summer Dormancy Is No Mystery

90821thumbCalifornia buckeye, Aesculus californica, is an enigma. How does it survive while defoliated for so much of the year? Not all are so mysterious. Those that live in sheltered or forested situations behave like normal deciduous trees, by defoliating in autumn, and refoliating in spring, after a brief winter dormancy. Those that are more exposed in warm and windy situations make us wonder.

After their brief winter dormancy, exposed California buckeye trees refoliate early in spring, as they should. Then, only a few month later, they defoliate through the warmest and most arid part of summer, which might be a few months long! As the weather cools and the rain starts, they refoliate briefly for autumn, only to defoliate in time for their winter dormancy. They are ‘twice deciduous’.

How do they photosynthesize enough to survive? It seems like they would consume more resources in this process that they could generate. They obviously know what they are doing, since they survive quite nicely in the wild. Furthermore, they are not the only species that can do this. Sycamores sometimes do it if the weather is just so, or if they get infested with anthracnose too severely.

Most deciduous plants defoliate only in winter because that is the worst time to try to photosynthesize. There is less sunlight available while the days are shorter, and the weather is cloudier. Frost, wind and snow would cause much more damage if deciduous plants retained their foliage. Defoliation is how they accommodate the weather. It is no different for plants that defoliate in summer.

Much of California is within chaparral or even desert climates. Native plants, as well as plants that are from similar climates, know how to live here. If they happen to be in a hot and dry situation, some may go dormant until the weather improves, even if they do not go dormant through the mild winters. This is why wild arums and some unwatered acanthus have died back to the ground, and why naked lady amaryllis will remain naked until the first rains in autumn.

What Bulbs Do After Bloom

90403thumbNarcissus, daffodil, freesia, snowdrop, snowflake, grape hyacinth, various iris and most other early spring blooming bulbs and bulb like plants should be perennials. We plant them with the hope that the will survive after bloom to bloom for another season, and perhaps for many seasons. Some should multiply to provide more bloom over the years. Bloom is just part of their annual cycle.

Lily, crocus, hyacinth, tulip, anemone and ranunculus are not nearly as likely to bloom more than one year for a variety of reasons. Some prefer more chill in winter. Some dislike the long and dry summers. Some survive as perennials, but do not bloom again. However, in some special situations, they also can bloom annually. After spring bulbs, there will be a different set of summer bulbs.

So, what happens after bloom? After exhausting much of their stored resources on production of bloom and foliage, bulbs try to recover and regenerate resources for the following season. Most work to replace their exhausted bulbs with comparable new bulbs. They need foliage to do this, but eventually shed their foliage as their new bulbs go dormant for the following autumn and winter.

Of course, they all do this at different rates. Some smaller bulbs are surprisingly efficient, and shed their foliage as soon as the weather gets warm later in spring. It is amazing that they can store up so much in such a minimal time. Other bulbs shed slowly, as their deteriorating foliage lingers for a few weeks into summer. Foliage of summer bulbs that bloom later is likely to linger until frost.

Because it is essential to the regenerative process, deteriorating foliage can not be cut back prematurely. It is not always easy to hide either. In mixed plantings, it might be obscured by ground cover or other plants. Alternatively, warm season annuals can be planted over the area. Some of us braid daffodil leaves, but others believe that braids draw attention to the deteriorating foliage.

Those of us who still dig and store and perhaps chill marginal bulbs, must wait for complete dormancy.

Sugaring Season

P90316KThere is no sugaring season here. Spring comes on too suddenly. By the time sap starts to flow, buds are already swelling.

Bigleaf maple, Acer macrophyllum, happens to be native here, although it is not common. It is the sugaring maple of the Pacific Northwest. A tree next to my driveway gave me enough sap to boil about four ounces of maple syrup a few years ago. That was all I needed to make the point to my colleagues who insisted that it could not be done that it really could be done.

Box elder, Acer negundo, is also native, and in riparian zones, is much more common than bigleaf maples is. I am told that is provides sap for sugaring just like any other maple does. Some say the sap is of inferior quality, or boils to cloudy syrup. Others say that it is comparable to that of any other maple.

Now that I made my point about getting a tiny bit of syrup from a bigleaf maple tree, I have no intention of sugaring again. However, sugaring season is still something that I need to be aware of. It is when I can not prune the maple trees. I can prune them earlier in winter or later in summer, but not while they are most vascularly active during sugaring season. Otherwise, they don’t stop bleeding. Even if the bleeding is harmless, it is unsightly if it stains the trunks and becomes infested with sooty mold as the weather warms.

The same rule applies to birch trees.

I pruned a few of the European white birch, Betula pendula, at work last week, believing that it was still too early for them to be too active. It was not much at all, and involved only a few small upper limbs and two significant lower limbs that had been disfigured by pruning for clearance from adjacent utility cables. I did not notice bleeding from the small stubbed limbs that I pruned from high in the canopy with a pole saw. Yet, the sap started to pour from the pruning wounds before I finished cutting away the two larger lower limbs that happened to be on the same tree. They are still bleeding now. In fact, they are bleeding so much that I feel badly that the tree is losing so much sap. If I had known how much sap would bleed, I could have put a bucket under each of the two wounds to catch the sap to make a small bit of syrup as is done in Alaska.

Plant Bare Root Plants Properly

90206thumbCompared to canned (potted) nursery stock, bare root plants have a few advantages. They are less expensive, easier to handle, more conducive to pruning into a desired form, and they disperse roots and get established more efficiently. One more advantage that is not often considered is that they are easier to install into the garden. For some, it is as simple as poking a stick in the mud.

Perhaps the only disadvantage of bare root plants is that they must be planted immediately, so that they get their roots soaked and settled into the ground into which they will disperse new roots. If planting must be delayed, roots can soak in a bucket of water for only a few days. Unless they are to live in big pots, potting for a season only delays and interferes with efficient root dispersion.

Only bare root trees that need root barriers (to divert roots from pavement) or mesh gopher baskets (to divert gophers from roots) will need planting holes that are as big as those for canned nursery stock. Otherwise, planting holes need be only as wide as the bare roots, and should be no deeper. If soil is loosened too deeply below, new plants will sink as loose soil settles. Graft unions must remain above grade.

Well flared roots can be spread over a cone of soil formed at the bottom of the planting hole. Conversely, cane berries, after their roots get loosened, can simply be dropped into slots formed by sticking a shovel into the ground and prying it back.

Soil amendments that are useful for providing a transition zone between potting media of canned nursery stock the surrounding soil are not so important with bare root stock. Bare root plants only want a bit of soil amendment if the soil is too sandy or too dense with clay. Otherwise, too much amendment can actually inhibit root dispersion by tempting roots to stay where the richest soil is.

Once planted, trees can be pruned as desired. Most come with superfluous stems to provide more options for pruning, and some stems will be damaged in transport. Fertilizer need not be applied until growth resumes in spring.