Bulbs for the Festive Season
I have a workshop tomorrow at the Nurseries where we will be exploring how to prepare, use and style with fragrant Paperwhite, Hyacinths and the drama that is undoubtedly the Hippeastrum (Amaryllis). These will add a richness and natural beauty to your homes throughout the Christmas period and in the weeks beyond, and especially after all the decorations have been packed away again and Spring seems still to be a long way off.
Some bulbs can be started right off indoors with no special treatment and you can choose a number of different ways to grow them and almost any container will do, with or without drainage. Paperwhites for example do not even need soil and with an anchoring layer of grit or pebbles, can be grown in glass jars, teapots and teacups or any ceramic container you like. You have to ensure that the bulbs have enough water but not so that it covers much more than the base plate (the flat bottom) of the bulb. I have grown them in hurricane lamps and have even grown them on moss, foregoing the grit.
Paperwhites are very forgiving and Amaryllis can be bought – appallingly – encased in wax, often glittery, so there is no way for you to even water them. Spare their feelings though and treat them a little better. Amaryllis need not be thrown out after flowering and with a little TLC which we will cover, will flower year after year as mine do. I have posted some articles on my personal blog and one in particular stands out – the display in the Glasshouse at RHS Wisley where there was a spectacular show of some quite amazing and dazzling varieties.
Many bulbs have been prepared to flower well ahead of their non-treated brothers and sisters and they have already had the requisite period of cold – and often dark – to fool them into thinking that they have already had their full compliment of winter weeks and months. These are labelled as ‘prepared’ and you can pot them up immediately, though I would do a little and often to avoid a glut, and then a famine. Prepared Hyacinths are especially fragrant, as with Paperwhite Narcissus, so a little goes a long way.
With the exception of Paperwhites, Amaryllis and prepared bulbs, most bulbs need between 10 to 15 weeks of cold to flower really well. The temperature, which should ideally be constant, somewhere between 1.5 degrees centigrade and less than ten degrees. This makes the bulb think it is winter and stimulates a biological response to initiate flowering.
Once they have been chilled, bring them in to somewhere warmer – above 15 degrees and they will sprout.
Buying bulbs early in the season, as soon as they are available which is often early September, you will have the best chances of forcing a host of bulbs and corms and having them bloom by Christmas – but if you are leaving it late, or are happy to have bulbs in flower in very early Spring, but still ahead of their time, buy prepared bulbs, or those that don’t need the cold and dark to get them going.
Paperwhite Narcissus are a perfect bulb to use – and a little does go a long way, as the fragrance is rich and quite powerful. There is a base note that stops it from being too sweet, but five or six bulbs will be enough to scent even a large room. I would stagger the planting and make up fresh pots over the coming weeks so that you will have a succession of flowers over many weeks, rather than a glut that will overpower your home and then vanish all at once.
There are three or four blooms on each stem. With blue/green strappy leaves that set off the pure white flowers perfectly. Double forms are available such as Bridal Crown, creamier in colour and with an egg-yolk yellow flash at the centre. These too are incredibly fragrant. We will be using Paperwhite tazetta Grandiflora today and looking at other bulbs – Hippeastrum and Hyacinth but touching on preparing other varieties for early indoor blooming.
Paperwhites do not need any especial treatment to get them to bloom indoors, they are a tropical narcissus and will bloom readily within the month, and the later they are planted, the more quickly they will flower. If you keep the bulbs cool and dark and plant them now, they will likely flower within 3-4 weeks; if you leave them until January, they may flower within just a fortnight. The flowers look good and last for up to 10 days, so it is useful to stagger potting them up to enjoy a succession of blooms.
They can, it has to be said, get quite leggy especially in warm, centrally heated rooms and where the daylight is less than strong. You can use twigs to help support their leaves and flower stems, and this can look very attractive, even before the green growth starts to sprout. A little raffia can encircle the greenery and keep it a little more upright too. I have included an article on some research suggesting than a little nip of alcohol might help – inhibiting the growth but not the flower performance or fragrance. Shorter, stockier plants that are more able to keep themselves upright.
Paperwhites I think are best in a group, and while Hyacinths can look good amongst company, they are also very likeable in single pots or glasses. The traditional glassware has a scooped neck that the fat bulbs sits in, with the base just touching the water level below. The roots will grow down into the water but it is not swimming and won’t rot. Amaryllis (though strictly are Hippeastrums) are magnificent on their own, but in a collection, they are amazing. I have six planted in a shallow, wide, copper jam pan – the variety is Appleblossom – and it was the centrepiece of the dining table when it flowered for over six weeks and then, after a pause of a month, flowered again.
Amaryllis are a perennial bulb, so after the flowers have faded, trim back the flowering stalk but encourage the leaves to form by feeding with a balanced liquid fertiliser. The bulbs can go outside after the last chance of frost and will enjoy a cool, shady spot for the remainder of the summer, potted in reasonable compost and watching out for slug and snail damage to the strap-like tender leaves. In late September, trim the leaves back, repot in fresh compost, keep dry and somewhere cool and bring indoors around now. The cycle begins again.
Please do keep your plants for the next season and they should continue to reward you with years of service. And please, avoid those encased in wax and glitter …. There isn’t a Society for the prevention of cruelty to plants, but sometimes I think there should be….
I have reblogged an article by Sarah Raven and also from the trials at RHS Wisley, which was a spectacular display.
I can thank the website The Spruce for the following two articles
https://www.thespruce.com/forcing-flowering-bulbs-for-winter-color-1402178
To force or not to force …
There are dozens of spring flowering bulbs that can be coaxed into bloom in mid-winter, when you really need them. Some require minimal effort, others require some pre-planning. Here’s how to get the best blooms from both types of bulbs.
No Pre-Chilling Required
Not all spring bulbs require a cold period. Some are actually only hardy to zone 8 or 9 and won’t survive a winter chill. In this category are some of the easiest bulbs to force, including amaryllis, freesia and tropical narcissus like paper whites. To coax these bulbs into bloom:
- Pot the bulbs, either in potting soil or water. If potting in water, either squeeze the bulbs tightly together in a shallow pot or anchor them with pebbles. Then pour in enough water to cover the bottom 1/3 to half of the bulb.
- The bulbs will sprout within a week or two of potting. Keep the sprouted plants cool (about 50 degrees F.) and in indirect light for the first 2 weeks, then move into bright direct light and provide more warmth. The plants should flower within 4 weeks.
If this sounds too easy, try forcing some non-tropical bulbs that require a period of prechilling before they will bloom.
Bulbs That Require a Chilling Period
Bulbs that are traditionally planted in the autumn need a period of cold temperatures to stimulate growth and flower production. These include: non-tropical narcissus, hyacinth (though they are available pre-chilled and labelled as Prepared), tulip and crocus. Doing it yourself takes planning, but not a lot of work.
Potting Up: Shallow pots are traditionally used for forcing and work well, but you can use most any container you choose. Fill the pot about 3/4 full with a potting compost (we use a wool based medium, where the wool is water retentive but not using peat).
Squeeze in as many bulbs as can fit. You can use all one type or mix and match. You can even plant smaller bulbs on top of larger bulbs, though try and pick varieties with a similar bloom time. Just be sure to plant the bulbs flat side down, pointy end up … Cover the bulbs with about one inch of potting mix. If you are planting tulips, leave the shoot tips poking out above the soil line. Water.
Temperature: Throughout the chilling period, the temperature needs to be around 35 – 45 degrees F. (This is an American article so will have to convert to centigrade!)
Duration: The period of chilling required will vary with the type of bulb, but most require at least 16 to 18 weeks. A little extra chilling won’t hurt the bulbs. However, if they aren’t allowed enough chilling time, the flower may not fully form. This means the bulbs should be kept where the temperature will not fluctuate greatly.
Location: If you live in an area where winters are cold, but rarely dip below 25 degrees F., (maybe zone 8), you can keep your potted bulbs outdoors. Place them in a convenient location and cover them with some straw mulch for protection.
Where winter temperatures are commonly below 25 degrees F., you can still chill your bulbs outside, but it will be more work. The bulbs will need to be in a hole or trench below ground level. A popular technique is to dig a trench about 2 feet deep and place your loose or potted bulbs in and cover them with a couple of layers of floating row cover or even old blankets. Then fill in the trench with a thick layer of straw or leaves. You will need to keep tabs on the temperature in your trench, to insure the bulbs do not freeze. If you have vole or squirrel problems, store the bulbs in wire mesh.
An easier method is to chill your bulbs in an unheated basement, crawlspace or attic, a partially heated garage or a cold frame.
You can also chill the bulbs in a refrigerator. This is the default method for those living in zones 9 and above. The catch here is that the bulbs cannot be stored where there is produce. Many ripening vegetables and fruits, especially apples, release ethylene gas, which can kill or damage the flowers.
Post-Chill: When the required chilling time is up, the bulbs should exhibit some root growth. Move your pots to a warm spot in your house, about 60 degrees F., with indirect sunlight. Shoots should emerge within a couple of weeks.
When the shoots are 4-5 inches high, the pots can be moved to brighter lit sunnier conditions and the temperature can be increased to 68-70 degrees F., to encourage budding.
When you begin to see colour in the buds, move your pots back to indirect sunlight. Remember, these are spring flowers and they aren’t happy in harsh light.
After the Bloom Fades: Forcing bulbs knocks them out of their regular routine and saps their energy. Most people simply discard the bulbs, once they’ve finished blooming. However except for the tropical narcissus, they can be saved and planted outdoors. Treat them like an outdoor bulb. Keep watering the plants and give them a little bulb food as the blooms fade. You should deadhead, but allow the foliage to yellow on its own. Then find a spot for them in your garden.
The plants should come back the following year, but it may take a few more years before they have the strength to rebloom. For a quicker payoff, try forcing tropical bulbs, like paperwhites and amaryllis. These bulbs need no prechilling and very little fuss.
Tipsy Paperwhites
Paperwhites (Narcissus tazetta) are deservedly popular indoor plants for winter. Unlike other narcissus, paperwhites don’t require a chilling period, so forcing them is as easy as putting the bulbs in water and waiting. The fragrant flowers bloom within about 2-3 weeks of planting, for almost instant gratification.
A problem with paperwhites, as with many bulbs planted in pots, is that they grow quite tall and all of their weight is at the top. Researchers in the Flowerbulb Research Program at Cornell University have come up with an unusual solution to this top heavy problem: Alcohol. When paperwhite bulbs are grown in a dilute solution of alcohol, the plants reach a height of 1/3 to ½ their normally expected growth – but the flowers remain normal size and last just as long. Why they thought of giving their paperwhites a nip remains a mystery, but it appears that the resulting water stress on the plants is just enough to stunt their growth, but not interfere otherwise.
How to Stunt Your Paperwhites with Alcohol
Pot your paperwhites in stones and water, as you normally would.
Once the roots begin growing and the green shoot on top reaches about 1-2 inches, pour off the existing water.
Replace the water with a solution of 4 – 6% alcohol, as described below. You should see results in a few days.
Continue to use the alcohol solution for future watering.
How to Make the Alcohol Watering Solution
- The alcohol content needs to be less than 10%, or your plants will overdose and severe growth problems will occur. Check the bottle for the percentage alcohol. Many liquors are only labelled as “proof”, not percentage of alcohol. Don’t confuse the two. To determine what percentage alcohol you have, divide the proof in half, So and 86 proof bourbon is 43% alcohol.
- You can use any hard liquor (vodka, tequila, whiskey…) or rubbing alcohol. Don’t use wine or beer because they are too high in sugar.
- You will have to do some math to get the different concentrations of alcohol down to 4-6%. To convert your booze to 5% alcohol, just divide the percentage alcohol by 5 and then subtract 1. That will tell you how many parts water to mix with your 1 part alcohol. Ex: 40 divided by 5 = 8: 8 minus 1 = 7… 7 parts water to 1 part alcohol.
Or simply use this chart: - Convert Existing Alcohol to a 5% Solution for Watering
10% Alcohol = 1 Part Water to 1 Part Alcohol
15% Alcohol = 2 Parts Water to 1 Part Alcohol
20% Alcohol = 3 Parts Water to 1 Part Alcohol
25% Alcohol = 4 Parts Water to 1 Part Alcohol
30% Alcohol = 5 Parts Water to 1 Part Alcohol
35% Alcohol = 6 Parts Water to 1 Part Alcohol
40% Alcohol = 7 Parts Water to 1 Part Alcohol …And so on.
The original article can be found here …
http://www.hort.cornell.edu/department/faculty/wmiller/bulb/Pickling_your_Paperwhites.pdf
I’d have a look at this website too –
https://www.gardenia.net/plant-variety/Paperwhite-Daffodils
Other subjects for forcing …
Anemones
Anemone coronaria will flower ahead of their time but you are still expecting a wait of ten to twelve weeks from planting. Soak the curious little things in tepid water for a couple of hours before planting. If you had done this in September, they would be in flower in mid-February, so probably this is one to put in your diary for 2019. Mix in some grit with the compost for good drainage – few bulbs like to sit in wet soil.
Plant just below the surface. Chilling might not be necessary, though a few weeks at about 5 degrees centigrade might improve your chances. They grow well in bright light and a cool spot, with evenly moist soil. They can be planted out into the garden subsequently.
Iris
Miniature Iris are perfect for indoor containers. Iris reticulata, Iris histroides and Iris danfordii can all be forced.
A loam-based soil lightened with some grit is ideal. For choice of container, these are small bulbs, so shallow bulb trays are ideal, but the bigger the better. Plant just below the surface of the potting medium. These irises need a spell in the cold to flower well, with a temperature below 10C for 10 to 15 weeks. They require 15 weeks in the dark. Keep compost moist. Planting to flowering 17 weeks.
Lily of the Valley – Convallaria majalis
These aren’t, strictly speaking, bulbs, but you can treat them in a similar way. There are few lovelier smells, and they grow well inside. For the bulbs, it doesn’t matter if they have begun to sprout. Soak in warm water for a couple of hours. These are small bulbs, but they have an extensive root structure. Tall, narrow pots are perfect and plant just below the surface of the soil. They are often pre-cooled when you buy them, so there is no need for a cold period. And this plant likes more moisture than most bulbs, so keep well watered. They don’t like bright light. Planting to flowering takes about three to four weeks. Subsequently plant them in the garden in a shady, moist spot and they will thrive. Do not cut off the foliage before planting. They may take a year to recover from the forcing process, but once they have settled in, they will last for decades.
Narcissi
As with hyacinths, a loam-based soil lightened with some grit is ideal and large, deep pots are ideal for their vast root structure, planting just below the soil surface. Narcissi need a spell in the cold to flower well, so keep below 10C for 10 to 15 weeks. They do not require time in the dark. Keep compost moist. Timing – planting to flowering Paperwhites take five to six weeks, others 16 to 18 weeks. Paperwhites are not hardy, so leave them in their pots for next year, or dry them off and re-pot them again late in the summer. Other hardy varieties can be kept or planted out.
The Teddington Gardener 