Category Archives: Forcing Plants

Planting Spring Bulbs Now…Yes It Is Possible

February 13, 2023 peterboroughmastergardeners 1 Comment

by Carol Anderson, Master Gardener in Training

Can spring bulbs be planted in late winter/early spring and still bloom? The answer is yes!

Perhaps you forgot to plant your spring bulbs in the fall (as is customary and recommended), it is better to take your chances now (late winter) and plant the bulbs rather than waiting for next fall as bulbs may not survive out of the ground this long.

Regardless of your circumstance, if you have “stray” bulbs still in your possession and they have been stored properly…you can “force” (or “trick”) your spring bulbs into blooming.

Bulbs can be divided into two groups, those that require a chill period, and those that don’t. For those that do require chilling, this chill period is less than what the bulbs would experience in the ground in a typical Ontario winter.

To force cold hardy bulbs into bloom you must first encourage them to produce new roots. This is accomplished by keeping them cool and moist for a period of time. Dropping the temperature during the cooling period to mimic the shift in soil temperatures that occurs naturally during the winter is a very effective method to encourage rooting, but can only be accomplished if you have the right set up (separate refrigerator, etc…).

Regardless, a proper cooling period that is around 40 degrees F (4.5 degrees C) throughout should be satisfactory to stimulate rooting and subsequent flowering.

Here is what you need to do:

Step	Notes
Ensure that those forgotten bulbs are still good.	If they have been stored in a cool, dry and dark location (and even better in a paper bag) they should be okay. Bulbs should be plump, firm and dry. Any sign of softness or evidence of mould signals that they are likely better in the trash can.
Pot the bulbs in a well-drained potting mix according to depth requirements for that bulb. Space the bulbs much more closely than you otherwise would have (almost touching).	Any pot can be used as long as there is 3-4” of soil under the bulb for rooting. It is recommended that “soil-less” potting mix is used as this allows excess moisture to drain away preventing potential growth of pathogens.
Water well and place in a cool dark spot (not freezing) for the required cooling period (see Table 1 below). Check moisture levels during this period and water if top is dry to the touch.	Although the ideal rooting temperature varies, most bulbs do best if stored at 40-60 degrees F for 3-4 weeks after potting, and then 32-40 degrees for the balance of the cooling period, mimicking the actual change in seasons. However, most bulbs will do well if the temperature is maintained close to 40 degrees F for the duration of the chilling period.
Check for rooting after the recommended chilling time.	Look for fleshy white roots in the bottom of the pots. Pots can stay in the cool zone until you are ready to bring them in of pot outside.
Bring the pots into the warmth/light in the house.	Ideally a sunny window in a cooler room (~65 degrees F). The bulbs think that spring has arrived and will sprout and ultimately flower in ~ 2-5 weeks.
Once the bulbs sprout and flower, they can be transplanted into larger outdoor containers outside.	They can also be transplanted into the garden directly at this point, maintaining the same depth
If grown in containers outside, remember that just like bulbs in the garden, allow them to completely die back (including the foliage).	Bulbs need all of the energy from the stems in order to replenish and store energy in the bulb for next years growth/bloom.

Note: Bulbs can also be chilled in a refrigerator where the temperature can be turned down after 3-4 weeks to truly mimic the changing seasons. However, ensure there is no fresh fruit in the same refrigerator as the ethylene gas produced can affect flowering.

Table 1. Recommended Rooting Times by Bulb Type

Bulb Type	Planting Depth	Cooling Period
Anemone	4 inches	8-10 weeks
Crocus	4 inches	8-10 weeks
Hyacinth	6 to 8 inches	12-14 weeks
Narcissus (Daffodil)	6 to 8 inches	14-17 weeks
Snowdrops	3 inches	10-12 weeks
Tulip	6 to 8 inches	14-16 weeks

Keep in mind that forced bulbs planted into the garden may not bloom the subsequent year. However, in the end, it may be better to try and “trick” your spare or forgotten bulbs into blooming this spring and enjoy them rather than take the chance that they are spoiled by next Fall.

Sources: www.whiteflowerfarm.com ; www.frustratedgardener.com ; www.halcyon-landscape.co.uk

Bulbs, Forcing Plants, Holidays, Houseplants

Your Amaryllis is NOT Just for Christmas!!!

December 12, 2022 peterboroughmastergardeners 4 Comments

by Carol Anderson, Master Gardener in Training

Amaryllis (Hippeastrum spp) is a beautiful flowering bulb that is native to South America. In Canada, we have traditionally considered it as “The flower of Christmas/Winter Bloom” and as such it is often given as a gift and sold during and for the holiday season.

Due to our harsh climate, the Amaryllis has been considered largely as an indoor plant that brings beautiful blooms (and great joy) into our homes during the cold and often grey days of winter. However, with some care, patience, and appreciation for the process, you can enjoy your prized Amaryllis for perhaps as long as 25 years (if you are lucky!!).

How to Enjoy Your Amaryllis Year Round

The trick to year-round enjoyment is ensuring that the Amaryllis bulb experiences a “cool period” (~50-55 degrees F) for 8 to10 weeks before attempting to bloom/rebloom. This “rest period” (not a true dormancy) is critical but can be accomplished through careful planning – enabling both a winter and summer blooming period to occur year after year. The Amaryllis can be enjoyed indoors during the winter months or in a spectacular garden display during the summer.

When to Grow Your Amaryllis

You can determine the best timing to plant, depending upon when you would like to enjoy the peak blooming period. The following timeline demonstrates the 3 critical periods and growth patterns for the Amaryllis. Understanding this timeline enables you to plan around when you would like to enjoy the spectacular blooms.

For example, a cool period from September through November, followed by a planting and a growth period from December through January will ensure winter blooms in January – March to bring life and enjoyment in the winter months inside your home.

Following the minimum “cool period”, you can consider when you would like to enjoy the blooms again, remembering that the bulbs require a warm moist growing period of ~ 8 weeks with bright indirect light before they will bloom again. Therefore, if planting outdoors to enjoy summer blooms, the bulbs may need to be started indoors where the temperature is warmer (70-75 degrees F) to stimulate the necessary growth of roots and shoots.

How to Grow Your Amaryllis

Here are some growing tips to ensure success:

Upon purchase or when coming out of the “cool period”, soak the bulb roots for 1-2 hrs in room temperature water to rehydrate the roots before planting.
Depth: Plant the bulb 2/3 under the soil with 1/3 above the soil line ensuring that the bulb is above the pot edge.
Soil: use a good nutritious potting compost that has good drainage (avoid peat to prevent moisture retention that could cause rotting).
Water sparingly until the stems appear, and then regularly
Light: bright indirect light; keep warm with a temperature 70-75 degrees during the growing period (Note: a lower temperature ~ 65 degrees once blooming will prolong the blooming period)
Staking: stems can grow >24 inches and blooms are “top-heavy”. Staking is recommended. Consider using a natural twig/dogwood staking mesh (see below) which can later be covered with evergreen/holy sprigs pinecones and cranberries for a beautiful table display.
Enjoy!!!!

Replanting

The leaves of the Amaryllis are needed to continue photosynthesis and replenish and store the necessary food/sugars in the bulb for future blooming…so remember to keep them intact until they die back. Some tips for replanting…

Remove old flowers right away (so that plant energy is redirected)
Trim stem to the top of the bulb when it begins to sag
Cut back leaves (only when they turn brown) to 1-2” above the bulb tip
Remove the bulb from the soil (new nutritious soil will be needed for regrowth)
Clean bulb of excess soil and store in a 45-55 degree cool, dark area until ready to plant. (Note: a fridge crisper can be used…but not if apples are present due to ethylene gas that could affect blooming).

Summary

Enjoying your Amaryllis blooms both summer and winter is possible for any enthusiast. Although it requires some planning and work, the pay-off can be extraordinary.

A mass planting with 10-12 bulbs (or more) outdoors in summer can be easily converted to beautiful indoor displays throughout your home during the holiday season – bringing joy and the anticipation for spring gardening into our hearts and minds during the deep winter months…

Forcing Plants

Invite Spring Indoors

March 7, 2022 peterboroughmastergardeners Leave a comment

By Marilyn Homewood, Master Gardener

As winter seems to drag on, why not have spring start inside by forcing blooms from some of your favorite woody plants?

Many ornamental trees and shrubs set their flower buds during the previous growing season. These buds must experience a period of dormancy (usually 6 weeks of cold weather) before they will open. As a rule, the buds will usually come out of dormancy within two to three weeks of exposure to warmth and moisture.

Coincidentally, late winter can be a good time to “clean up” deciduous trees and shrubs. Prune plants lightly by removing crossed branches and old or diseased wood keeping in mind to leave some buds to bloom in the garden. From the cuttings, select out branches of less than ½ inch diameter for forcing and trim them to a manageable length.

Pruning is best done on a mild winter day when the temperatures are above freezing. The branches and buds are softer and more pliable and transition from cold outdoor temperatures to the indoor temperatures more readily. Try to select branches that seem to have a lot of plump flower buds. In general, flower buds are round and fat, whereas leaf buds are smaller and pointed.

Once inside, recut the branches to open up the vascular system of the branch and encourage water uptake. Woody branches do not take up water as easily as green flower stems so they should be cut at the end of the stem for roughly an inch or so with sharp pruners.

Larger diameter branches can be cut twice at right angles. Place the branches into a bucket of warm water to rehydrate. Keep the bucket in a cool, dark place overnight to allow branches to rest (this also helps them to transition from the outdoors).

After resting, prepare a vase of fresh water for your branches and recut the stems again before placing in vase. Adding a few drops of bleach to the water will help keep bacteria from multiplying in the water and plugging up the vascular system. Place your branches in a bright, cool place away from direct sunlight.

Changing the water every few days is recommended. The time taken to bloom depends on when the branches were harvested. Branches harvested in mid-winter can take 2 to 3 weeks for flowers to open. Branches harvested in late winter will bloom in 7 to 10 days.

After blooming, keep the branches away from direct sunlight and away from any direct heat source, which will dry out the buds and branches and reduce overall bloom color and quality. Ideally, try to duplicate the cool, moist environment of the spring. Once in flower, branches should last in the vase for 10 days. Changing the water frequently and adding flower food will also help to extend their life.

Some of the species that force well are forsythia, fothergilla, witch hazel, ornamental pear, cherry, birch (for catkins), eastern redbud, lilac, magnolia, serviceberry and willow (for catkins). Or try experimenting. I have some Red Osier Dogwood in a vase at the moment. The red stems are attractive and although I expect to get foliage perhaps a few tiny flowers may appear.