Spring-Flowering Bulbs: So Easy to Plant!


Garden centers offer plenty of spring-flowering bulbs in the fall.

Tulips, hyacinths, daffodils, crocus and other spring-flowering bulbs: garden centers sell them by the shovelful each fall. And their culture is super easy. Dig, drop, done, as one promoters put it. But still, if it’s your first time, here are a few details about planting hardy bulbs you might find useful:


Between September and November in the Northern Hemisphere, up to 2 weeks before the ground freezes definitively.


In rich and particularly well-drained soil. If your soil is heavy clay and/or stays soaking wet in spring, you won’t succeed with most bulbs. Instead, plant them in a raised flowerbed.

Where the spring sun shines. Of course, that can be a spot that is in full sun all year long, but since spring bulbs grow, flower and die back before trees have fully leafed out, you can also plant them under trees in places that are sunny in the spring, but shady during the summer.

Spring bulbs need a cool to cold winter and many won’t be happy in zones 9 and above. In Florida, for example, tulips have to be grown in refrigerators and planted out once the artificial cold has helped them root properly. On the other hand, most bulbs are very hardy and will thrive to hardiness zone 3, especially if you cover them with mulch in the very coldest regions.



Dig a hole 3 times as deep as the bulb is tall and space the bulbs at 3 times their diameter.

Dig a hole three times as deep as the bulb is tall. Make an exception for tulips: if you want them to return faithfully year after year, plant the bulb 1 foot (30 cm) deep. That will only work in well-drained soils, though. See Where? above for more details.

If your soil is on the heavy side, you can can lighten it by adding about one third compost to the soil you dig out.

It is easier to dig a large hole for several bulbs that individual holes for each bulb. For an attractive look, try 10 bulbs or more per hole in the case of larger bulbs, such as tulips, daffodils and hyacinths, and 15 to 25 bulbs per hole for small bulbs (crocus, muscaris, snowdrops, etc.).


Add a bit of slow-release fertilizer to the soil.

Add bulb fertilizer or another slow-release organic fertilizer to the planting hole. Follow the dose recommended by the manufacturer. Also, adding a spoonful or two of mycorrhizae fungi (beneficial fungi) to the bottom of the planting hole can be useful if you’re working with soil that has been disturbed or has just been added.

Do not use bone meal as a fertilizer. Yes, I know, many garden centers still put it out with bulb displays as if it were the ideal bulb fertilizer, but they’re basing this on old-fashioned, nitrogen-rich bone meal, a product that hasn’t been available in generations. Bone meal as presently sold essentially gives nothing to your bulbs and attracts vermin that may dig up your bulbs. Read Bone Meal: Much Ado About Nothing for more information.

Place bulbs with the flat side down and the pointed side up. Some bulbs have no clear up side and down side: just plant them any which way: they’ll adjust themselves.

Space the bulbs about 3 times their diameter.

Fill the hole with soil.

Tamp down gently.

Water well.

You can cover the spot with mulch, but that isn’t absolutely necessary.

What About Squirrels?

Squirrels, chipmunks and voles like to dig up and carry off bulbs of tulips and crocus, especially if you marked the spot where they are planted with bone meal. To learn how to keep them away, read Protecting Bulbs from Squirrels.

You’re Done!


Spring bulbs: plant in the fall for spectacular spring bloom!

There you go, you did it! Just leave them alone now: your job is done!

During the winter, your bulbs will grow underground – yes, even under the snow! –  in order to get ready for the flowering to come. As soon as the snow melts, up they come and soon they soon be in bloom. Ain’t nature wonderful?20160926b

Plant in Almost Any Season


You can plant in almost any season. Photo: USFS Region 5, Creative Commons

Beginning gardeners often worry about when to plant the plants they buy, yet the answer is simple: pretty much any time you want to.

You can plant almost any time the ground isn’t frozen. That said, the two most popular seasons for planting are spring and fall (in the latter case, until about 2 weeks before the ground freezes for the winter), while the plants are more or less dormant… and when cooler temperatures mean digging holes is not as arduous for you.

Special Cases

Of course, some plants do have special needs.


Spring-blooming bulbs are planted in the fall.

Annuals, tender bulbs and most vegetables, for example, must be planted in the spring, of course, as they don’t survive the winter in most climates. As for hardy bulbs, including tulips, daffodils, and hyacinths, but also garlic, fall is the best time.

For most other plants, take your pick: either season is appropriate. In cold-winter regions, however, it is better plant slow-rooting plants such as rhododendrons and magnolias in the spring so they’ll have time to settle in and produce new roots before winter comes. You can however plant them in the fall as well as long as you mulch them thoroughly after planting.

Summer Planting

I haven’t mentioned summer planting yet, although it is perfectly feasible, especially for plants grown in pots (as opposed, for example, to bare-root plants) since their rootball is left intact when you plant. Plants put in the ground during hot weather may need extra watering to settle in, but otherwise do fine.

Bare-root plants will find it a bit more of struggle if you plant them in the summer, as they have fewer or damaged roots and tend to wilt on hot days, but should do fine as long as you keep their soil moist until they show by new growth that they have settled in.


Summer planting is harder on the gardener than on the plant.

The main reason not to plant in the summer, though, is for your sake: planting during hot, humid weather is simply uncomfortable for the gardener!20160925a

No Night Light for Short-Day Plants


The Thanksgiving cactus is a short-day plant that blooms about a month before Christmas cactus. It needs short days in order to bloom.

The vast majority of plants we grow in our homes are more or less indifferent to daylength (they are day-neutral) and are able to bloom at any time of the year. Since light is more abundant in the spring and summer, however, they do tend to bloom best at those seasons.

However, there is a small group of houseplants that need short days in order to flower. These plants will not flower under the long days of summer, but rather begin to bloom in the fall or winter, when days are less than 12 hours long. They are called, logically enough, short-day plants.

In nature, these plants usually come not from the equatorial zone, but from areas north or south of the Equator where there is at least a small difference in daylength in what is locally the fall. When days are shorter than 12 hours, they will naturally start to get ready to bloom.

Just a Few Choice Plants

The list of short-day houseplants is not very long. It includes is the poinsettia (Euphorbia pulcherrima), Thanksgiving and Christmas cactus (Schlumbergera spp.),  Christmas kalanchoe, including the popular double Calandiva varieties (Kalanchoe blossfeldiana and its hybrids), most rhizomatous begonias (Begonia spp.), at least one bromeliad, queen’s tears (Billbergia nutans), and quite a few orchids. Many but not all cultivars of Phalaenopsis and Cattleya, for example, will bloom in late winter or early spring, but their bloom is stimulated by shorter days the previous fall.


The florist’s chrysanthemum is not a good houseplant, but is more a temporary indoor decoration. It blooms under short days.

The florist’s chrysanthemum (Chrysanthemum x morifolium) is often included on lists of short-day houseplants and is indeed a short-day plant, but you could hardly call it a true houseplant! Instead it is more a garden plant or cold greenhouse plant you buy already in bloom to use to decorate your home. It dies pretty quickly in most indoor environments.

If you want to bloom a chrysanthemum to decorate your home, pot one up in the fall and leave it outside under the naturally short days found there, then bring it indoors to enjoy when the first flowers start to open. Have no fear: it is highly tolerant of cold and won’t mind being outdoors in the often chilly weather of October and November.

Getting a Short-Day Plant to Bloom Indoors

To bloom a short-day houseplant, place it in a sunny window in a spot that receives no artificial light at night, starting at the beginning of autumn (day length begins to decrease to less than 12 hours a day beginning at the fall equinox, that is September 21st or 22nd).

You can also grow them in a room that is illuminated at night as long as their location doesn’t receive too much artificial lighting. For example, you can place a panel of some sort between the plant and the source of artificial light or set it behind another plant that blocks any evening lighting.


The poinsettia is extremely sensitive to any interruption in its short-day regime. Even headlights from passing cars can cause its blooms to abort.

The degree of sensitivity to artificial light does however vary according to the type of plant. The poinsettia is highly sensitive to the slightest amount of artificial light and just a few seconds of nighttime light at the wrong time can cause its blooms to abort. Thanksgiving and Christmas cactus and the various rhizomatous begonias, on the other hand, are much more accommodating and often bloom well in a room lit at night as long as only a modest amount of artificial light reaches them… or may bloom only on the side of the plant that wasn’t exposed to evening illumination!

Blooming Twice?

Sometimes short-day plants bloom a second time during the winter, towards spring, at least in northern regions. That’s because the days in high latitude regions remain short for months on end and the plant, used to only a limited period of short days in the wild, sometimes reacts to these extra-long periods of short days with a second wave of flowers.

How Not to Get a Short-Day Plant to Bloom Indoors

The Internet if full of false or misleading information about gardening. One example you sometimes see is the suggestion that you can get short-day houseplants to bloom by putting them in a closet for 2 or 3 months in the fall.

True, this does ensure short days (I mean, you can’t get shorter days than 0 hours of light a day!) and if the plant survives, it may bloom, but such a radical treatment is very harmful to the plant, eventually killing it or at least weakening it terribly. Which would you rather have: a half-dead plant with a few flowers (closet treatment) or a healthy plant in full bloom (the no-light-at-night treatment)?

Time for Action

Each fall, place your short-day plants in a brightly lit spot with no extraneous artificial light starting in late September or early October, keep watering it normally and you’ll be rewarded with a beautiful blooming few months later, often in time for Christmas. Yes, it is that simple!20160924a

Flush Plant Roots Before You Fly




You can’t just stuff a living plant into a carry-on bag and expect it to be in fine shape when you arrive home.

You’re traveling far from home and you see a plant you just can’t resist. A perennial you simply can’t find in your local nursery, for example, or a small shrub you’ve been seeking for years. But you’ll be flying home with only a carry-on bag. How can you bring it back in good condition without having to buying a new suitcase… or arriving home to find your bag full of freshly liberated potting soil?

Bare Root is the Secret

In general, the easiest way to bring a plant home by plane is bare root, that is, by first removing its heavy, messy soil. And it’s so easy to do!

First, though, find a plastic bag large enough to slip the roots into, plus a few sheets of newspaper. The hotel where you’re staying ought to be able to find them for you.


Just flush that annoying soil away!

Now, the night before returning home, remove the plant from its pot, plunge its roots into the toilet bowl and flush it while swishing the roots back and forth. Repeat if necessary. You want to remove as much soil as possible, especially if you will be crossing a border (in some cases, you can bring the plant back, but not the soil.)

(Don’t be squeamish! Toilet bowl water is perfectly clean, as clean as the tap water in the nearby sink… but don’t try to rinse plant roots in a sink. The drain won’t be able to handle soil and you’ll end up plugging it!)

Once the roots are as soil-free as possible, give the plant a good shake to remove most of the water. Then wrap the roots in a towel and squeeze very lightly, just enough to remove excess moisture (you’ll want the roots to be barely moist). Remove the towel and place the root ball in a plastic bag to keep it from drying out during your trip.


Wrap the branches tightly in newspaper.

In order to do the least amount of damage possible to the foliage during transit, wrap the plant in newspaper, rolling it tightly to pull the branches upward into a bunch.

You’re now good for a trip lasting from a few hours to up to a week or so (several weeks in the case of orchids and succulents, as they are especially good at tolerating travel).

When you get home, remove the newspaper and plastic bag and plant your discovery in the garden (or repot it if it’s a houseplant), then water well.

It’s as simple as that!

Plants Across International Borders

It’s best to consider reserving the technique described above to situations when you are travelling within your own country. Without an import permit and a phytosanitary certificate, it is almost always illegal to import living plants from abroad. Even within the US, some states, like California, Arizona, and Florida, may require plants undergo inspection or have proper permits before bringing them into the state.

Canadians can however bring houseplants back from the continental United States and Hawaii, although there are a few exceptions. Check here for current information: Plant protection import requirements for plants and plant parts for planting.

Also, plants can travel freely between the countries of the European Union (between Italy and France, for example), but there are restrictions on the movement of certain plants from certain areas because of localized disease or insect infestations. The nursery where you buy the plant should be aware if the movement of any of their plants is in any way restricted.

Bon voyage … and happy gardening!2016023a

Don’t give poinsettias the cold treatment


It’s time to start preparing your poinsettia for Christmas bloom. Photo: Andy Mabbett, Wikimedia Commons

When fall officially starts, it’s time to start preparing your poinsettia (Euphorbia pulcherrima) for its Christmas bloom. Its flowering is stimulated by short days, that is days less than 12 hours long. (Actually, it’s the nights longer than 12 hours that stimulate bloom, but let’s not quibble over details, as the results are the same.) So anything that reduces day length in the fall, while still maintaining viable conditions (warm temperatures, occasional waterings, etc.), will probably give good results. It really will bloom again for Christmas, year after year, if you just give it a chance.

However, anything that artificially extends day length, such as growing it in a room you keep lit at night, will prevent it from blooming.

The “Put It Outdoors” Method

Some Internet sites suggest that the best way to get a poinsettia to rebloom is to put it outside in the fall (or to leave it outside if you had already put your plant out for the summer) and to leave it there until the bracts start to change color. And that certainly sounds easy enough to do. After all, it will automatically receive short days outdoors from September 22 on (thank you Mother Nature!). So unless you place it near a lighted window, street lamp or other source of night illumination that will artificially extend day length, it really ought to start changing color in November… and once the color change is initiated, it will continue even if the days are no longer short. So you can bring your just-starting-to-bloom poinsettia indoors where it will complete its blooming cycle.


Leaves dropping shows your plant is reacting badly to the change.

There is a major flaw with this technique, though. Poinsettias are all right at fairly cool temperatures, but dislike cold (less than 45˚F/7˚C) and frost will kill them back to the base, if indeed it doesn’t kill them outright. So if you live in an area where temperatures can dip below 50˚F (10˚C) in October or November, and that would cover all of pretty much all of North America north of Florida as well as all but the Mediterranean region of Europe, leaving poinsettias outside in the fall is inherently risky.

But it’s not just the risk of cold or frost you have to consider.

Poinsettia plants that acclimate to cool fall temperatures outdoors tend to shed their leaves massively when you do bring them back indoors. They find the transition from cool conditions to warm ones a severe shock. So yes, your plants will bloom, but sans most of their leaves. Not too charming an effect!

The Easy Way

To get a poinsettia to bloom with a full cohort of leaves, first bring it indoors early in the fall, while night temperatures indoors and out are pretty much equal. That way the plant will already be acclimated and won’t lose leaves. Then all you have to do is to give it short days indoors (and keep watering it, of course)… and that’s a snap. To learn how, see Blooming a Poinsettia the Laidback Way). Try it: it really works!

Can You Harvest the Seeds of Hybrid Plants?


Fall is the season for harvesting the seeds for next year’s garden.

If you’re into growing plants from seed, especially vegetables and annuals, you’ve undoubtedly been warned you’re not supposed to collect seeds from hybrid plants. But why?!


Hybrids are generally produced by meticulously hand pollinating one plant with another.

It’s because hybrids are the result of crossing of two different parent plants. Because of their mixed background, the seeds produced by these hybrids will not be “true to the type” (identical to their parent) in the next generation.

For example: when you cross a pure line of white petunias with a pure line of red petunias, the first generation (known as the F1 generation) gives uniformly pink petunias and that may be the desired goal. But if you harvest the seeds of these pink petunias, in the next generation (the second or F2 generation), there will still be pink flowers, but the genes of the grandparents will also show up and you’ll also get a certain percentage of white flowers and red flowers.

And it’s not just the color that won’t be true to type: the plant’s size, the number of flowers, the taste (if it’s edible), its disease resistance and in fact almost any characteristic of the hybrid may show up differently in the F2 generation.

Well, Can You or Can’t You?

So let’s repeat the question: can you harvest the seed of hybrid varieties?

Yes, of course you can… if you’re not stuck on the principle that the next generation must absolutely be identical to the previous one.


The F2 generation from a strain of F1 petunias: the results are mixed, but most are pretty nice plants.

Often when you sow the seeds of hybrid plants, you end up with some really interesting combinations of characteristics… but also some rather unfortunate ones. But by weeding out the undesirable plants and annually harvesting the seeds of plants that you judge the very best, you can eventually develop your own seed line that will probably, after some years of selection, be true to type.

So the choice is up to you: if you prefer trustworthy results from a hybrid seed-grown plant, buy fresh seeds when you run out, but if you like to experiment, go and ahead and sow what you reap!

Surprising Facts: Bamboos are Grasses


A bamboo forest in Asia.

Despite their size, the bamboos are grasses, that is, they belong to the Poaceae, like the grasses in our lawns and the wheat in our fields. Unlike conventional grasses, however, their stems are woody and persist from one year to thenex, so we could describe them as being “woody grasses”.

The tallest of the bamboos, Dendrocalamus giganteus, a tropical Asian species, can reach up to 160 feet (50 meters) in height, equivalent to a 15 story building. It is also the fastest growing plant in the world, reaching up to 3 feet (90 cm) per day.


Pygmy bamboo

On the opposite end of the scale, the smallest bamboo, pygmy bamboo (Pleioblastus pygmaeus) doesn’t exceed 8 inches (20 cm) in height, at least when grown in full sun, and can in fact be used as a no-mow lawn. Among the most cold-resistant of all bamboos, it will grow in hardiness zones 4 to 10.


Japanese knotwood may have hollow stems like a bamboo, it is not a grass at all.

Note that the pernicious weed sometimes called Mexican bamboo, American bamboo or Quebec bamboo, Fallopia japonica, is not a bamboo at all, but belongs to a very different family, the Polygonaceae or buckwheat family. It is more correctly referred to as Japanese knotweed.20160920a