Why No Flowers?

Question:

I live in south-east Ontario, near Peterborough and found several bulbs in my garden this spring that were planted by the previous owner of the property. They are 2 to 2-and-a-half inches in size and had quite thick roots. The foliage was about 8-10 inches tall, the colour of daffodils and the leaves very similar too…but less pointed. They didn’t flower. Have you any idea what they might be? I am enclosing shots of the plant and hope that you will be able to use them.

Answer:

It does look to me like those are daffodils you have in your garden. Of course there are many bulbs that have that same foliage and habit, and without a flower IDing them can be tough. As far as why no blooms, my best guess is that it has to do with the nutrients in the soil. Certainly there is enough nitrogen in the soil. Nitrogen is one the macronutrients that a plant relies on, and it helps a plant to produce healthy green foliage and photosynthesize. Another macronutrient that plants rely on is phosphorous, and adding phosphorous to the soil typically helps a plant to produce a larger and more profuse flower. Having a number of bulbs produce foliage but no flower I’m guessing there is either not enough sun or not enough phosphorous. From the photos it seems like the bulbs are getting plenty of light and they ought to be flowering. So, therefore, this is what I would do. This fall when your local garden center or nursery puts out all of their bulb displays, look at the fertilizers they are selling. Each fertilizer has three numbers printed on the label, and those are the percentages of nitrogen, phosphorous, and potash (potassium) respectively in each dose. What you want to find and apply to your yard is a fertilizer with a high middle number. I am guessing you will most likely find it in a granular form. You can apply it this fall and it should break down and leach into the soil over the winter months so that as the roots of the daffodils begin to grow early spring they can get the much needed boost and then go back to their flowering selves. Of course, if you feel your soil has been properly amended and has all of the necessary nutrients then it might be worth getting a soil test done. In fact, if it is a new property a soil test is probably worth doing regardless. It can help you avoid a lot of guessing in the long run.

Planting Perennials with Spring Flowering Bulbs

Over the last year-and-a-half I have been consulting and coaching a gardener and HSNY member in Rego Park, Queens. I make seasonal visits to advise on new plantings to add, transplants to perform, pruning to consider, plant and weed identification, and the like. Not only am I thrilled with how the garden is coming along, but the owner has become really educated and empowered herself, and that is what is most gratifying to me. She had embraced and prioritized horticulture in her own life and every time I visit it is wonderful to see how she in return is positively influencing her neighbors and their gardens. Just the same, questions always arise, such as the following which came in a recent email. As always I am more than happy to further educate and empower to the best of my ability. If you have a garden space and need the advice of a professional horticulturist let me remind you that HSNY does provide a consultation service for residents in Manhattan and the outer boroughs. Feel free to email me for more details at afeleppa@hsny.org.

Question/concern:

I did do one probably bad thing Sunday. I couldn't resist some shasta daisies and then couldn't find a sunny spot to plant them so in desperation put them among the tulips (there are two big bunches, which I later realized I probably should have broken up). Now I'm concerned that the tulips and daisies will be fighting for nutrients and water next spring, will they?

Answer:

Not necessarily a bad move to plant the daisies among the tulips. Yes, you could have broken them up and planted them interspersed instead of in large clumps, but as we have discussed I know how the clumps make more of an impact in your garden so it is fine to enjoy them that way. Often spring flowering bulbs are active and then dormant at different times than many perennials. Up at NYBG they have a fabulous daylily/daffodil walk, a long expanse with the two different perennials planted in large clumps right next to each other. The daffodils do their thing nice and early in spring as usual and as they go dormant for the summer the daylilies really come into their own and then flower through the summer months. Bulbs do not need nor want tons of excess moisture during the summer, but the day lilies end up taking most of the water for themselves so it turns out that the two co-exist quite happily. Your situation is slightly different, but I think the basic factors remain the same. Your tulips have already pushed their flower and foliage. Now we are just letting the foliage remain to build up energy and nutrient reserves for next year. As those leaves will soon yellow and the bulbs will begin to go dormant the daisies will begin to enjoy the spotlight, including the sun and the regular watering you provide. Next spring the cycle should repeat itself, with the bulbs active early followed nicely by the daisies. In a couple years we might have to plant some new tulips as they only seem to last 3-5 years comfortably, and by that time we can plant them in more concentrated clumps between the daisies to keep the look and feel of your garden sensational.

Planting bulbs and microclimates (A Word of Thanks)

(lily-flowered tulips like these 'Queen of Sheba' were among the many different varieties of tulips and daffoldils planted at the 96th Street branch of the New York Public Library by local teenagers)

Yesterday I had one of those days that reminded me why it is so important that we do what we do here at The Horticultural Society.

As people were bundled up and ducking inside or underground to avoid the cold and falling snow I was preparing to do just the opposite. Melissa Fisher, Director of our GreenBranches program, was busy installing a new GreenBranches learning garden out in Whitestone, Queens, and she had asked for my help. As part of our GreenBranches programming we plant bulbs in the fall with young children and teenagers at a number of our library gardens throughout the city. The recent weather was keeping the Whitestone installation on a tight schedule and Melissa had phoned to ask if I could run the workshop planting bulbs with teens up at the 96th Street branch of the New York Public Library here in Manhattan. Luckily my schedule for the afternoon was free of meetings so I said, “of course”, got the details from Melissa, and was on my way.

Well, as the afternoon rolled on I must admit I began to get nervous. I began to fear that the ground would be too frozen to plant, and I wondered what I was going to do with the hundreds of tulips and daffodils. The workshop was scheduled from 3:30 to 5:00pm and as the temperature continued to drop I then feared that no teens would even show in the first place. Certainly the looks of complete bafflement I received from the bundled commuters didn’t help, but I continued to swim upstream with my big bag of tools and reinforced steel shovel.

I arrived at the 96th Street Library, and it was amazing how my fears began to melt away. It was actually my first time at the 96th Street branch and entering the small backyard garden it looked so beautiful with the fresh dusting of snow on the evergreens. I always refer to our GreenBranches gardens as real oases here in the city, and this was no exception. I pulled a trowel from my bag took a stab at a piece of barren soil between a rose and some bergenia. To my surprise the ground was soft and the trowel penetrated the soil easily. I stood back and began to laugh to myself. Of course, I thought, microclimates! How could I have been so foolish?!

In the midst of getting myself worked up I had forgotten one of the basics. Here in the city we always have to consider microclimates. To understand microclimates in the city we have to take into account all the abiotic factors here in the city that might affect our gardens. Abiotic factors are nonliving, often man-made factors that affect our natural environment. For example the positioning of a terrace on the 20th floor that faces the water might be much colder and windier than your typical garden plot on the ground. Equally so, a backyard garden surrounded by large heated buildings might have slightly warmer soil temperatures compared to if it were out in the open. Microclimates are not to be thought of as being good or bad, but we certainly must consider them when discussing or performing urban horticulture. In this case the presence of a microclimate was to our advantage.

A few minutes later I was happily proven wrong a second time as a number of young teens joined me outside and asked what we were going to be doing for the afternoon. Wired on their large cups of hot chocolate these kids were amazing. After explaining what bulbs are and how they grow the boys and girls couldn’t wait to get planting. We laid out the bulbs, tulips and daffodils to flower from early- to late-spring, and we all got busy planting. Eventually the darkness forced us to quit for the evening, but not before we planted a couple hundred bulbs in this little oasis behind 96th Street. I was reminded how fearless kids can be and I felt I was learning just as much as they were. Furthermore it reminded me of the power and value of horticulture here in the city, and how important it is that we engage everyone to make this a greener, healthier, and happier place. I know those kids will be keeping a close eye on the GreenBranches garden at 96th Street, and I can’t wait to hear and see their reaction next spring. Even more I can't wait for those kids to continue to learn and grow, knowing how they will influence others to embrace horticulture in our city. Thank you to the amazing staff at the 96th Street library, the kids who now know and care about the importance of gardens and plants, and all the members and supporters of HSNY who make these programs possible.

Moving Iris Corms Upstate?

Question:

We are planning a move to upstate NY, around Utica. I am bringing some iris corms from Oregon and am wondering how to take care of them and grow them in NY's climate. Any ideas? resources? Thank you.

Answer:
Thanks for writing. Since you are moving from Oregon, where the climate is milder for the most part, it might be worth double-checking that your corms are going to be cold hardy to zone 5 or even colder, zone 4. If you know the species of iris you are bringing I would imagine most references will be able to tell you their cold hardiness. That being said, I would simply get them in the ground when you get here. As long as you can pierce the ground I would plant your corms about 4" down in a spot with ample sun and soil that is well draining. If you are dealing with larger bearded iris then those rhizomes need to be planted much shallower, with the top 1/3 or 1/2 of the rhizome above ground. Again, it might be worth checking the cold hardiness first. Either way, planted in the fall your iris should be able to establish enough of a root system to perform well for you next summer. As far as references to use, the American Horticultural Society puts out a number of books through DK publishing that I consider excellent reference books across the boards. They are even getting more specific with regional books and they do have one specifically on the northeast. Otherwise, when you get here ask you local garden center what books they use as references. Regarding the internet I like a website called gardenweb.com and can easily spend days reading about everyone's experiences, successes, etc.


In related news, I will be teaching an informal demonstration class on planting bulbs in containers tonight at the HSNY headquarters from 6-7:30. I will be discussing planting bulbs both indoors and out and there will be a little hands-on demontration towards the end. This program is free for HSNY members and $10 for nonmembers.

Peonies, Crocus, and Corylus: A work in progress

(image of an unknown peony cultivar (Paeonia sp.) I took at Tower Hill Botanic Garden, 2006)

I have recently received a number of excellent questions. I am calling this a "work in progress" because I am still researching and trying to find answers, but I wanted to share with you what I have found to date.

Questions:
1 - I have 2 peonies - one of which I divided from the original. In the spring they show lots of buds with ants crawling happily all over them but only 4 or 5 of the buds actually flower. They're about 7 years old, in full sun, I fertilize them w/ bone meal in spring & fall, I prune them back to about 5 inches each autumn. What am I doing wrong?
2 - I started with about half a dozen bulbs for autumn flowering crocus (sativus). The bulbs proliferate - I have dozens now - & they put up plenty of foliage but only 2 or 3 bloom.
3 - I have a new Harry Lauder Walking Stick that I planted in April. It's growing much faster than I anticipated - from a foot, it's more than doubled in size. Is it o.k. to prune it &, if so, when is the best time to do it?

Answers:

Regarding the peonies (Paeonia spp.) not blooming:
There is an old wives tale that peonies do not bloom for seven years if you transplant them. It is true that the roots hate to be disturbed, but as long as the crown buds were planted 2-3 inches below the soil level they should bloom the following year. This fall when you do cleanup perhaps you will want to excavate a little and see where the new buds are situated to make sure they are not too high or too deep. If the buds set and then we are hit with a late cold spell some of the buds can get blasted and never flower, but if this is happening year after year it seems safe to rule that out as a possible cause. Your cleanup practices seem appropriate; when I see them begin to die back I cut them flush to the ground and rake the area clean. Even though bone meal is recommended, I wonder if applying it in the fall and spring is a bit much. Because it is slow release, I would apply in the fall, but in the spring maybe you can just stick to just using compost. Peonies tolerate a wide pH range in the soil (6.0 – 7.0) and I have even seen them happy in slightly more acidic soil, so I wonder if the bone meal has slowly made the soil too alkaline (a pH of greater than 7). Have you ever had your soil tested? You can see why I want to research this question more.

Regarding the non-flowering Crocus sativus:
Fall-blooming Crocus love full, baking sun so if shade has slowly crept in the area that might help to explain the lack of flower. Taylor’s Guides state that Crocus sativus can lack flower if the summer is too cool and wet. I had thought Crocus preferred an evenly moist summer, but perhaps this species prefers a dryer summer. Of course, well-drained soil is a must, and added compost never hurts. You have mentioned that the bulbs are doing well, but have you divided them? For this species of Crocus, you want to lift and divide the corms every 3-4 years as the foliage begins to fade and die back naturally. Plant the divided corms about 3-4” deep, safely below the frost line, but do not plant them as deep as the 6” some may recommend.

Regarding the Harry Lauders Walkingstick (Corylus avellana ‘Contorta’):
I would take all the new growth as a good sign that the tree is establishing plenty of new roots as well. As you may have experienced when planting, these small trees have a very large root system given the relative size of the tree itself. I used to study under an arborist I admire greatly and he never recommended pruning newly planted trees until two or three years in their new location. The fundamental thinking is that pruning causes the tree to work harder to callus those cuts, and while getting established you want to stress the tree as little as possible. That being said, if you feel you need to prune it at this time, I recommend pruning this tree in late winter or early spring. Prune only what you have to maintain shape or remove dead, diseased, or damaged wood. Remember that your tree uses the majority of its stored energy for the process of leafing out in the spring, so again we want there to be as little added stress as possible. In the long run you should know that Corylus avellana ‘Contorta’ will reach 10’ or more in height and width at maturity. Over time the tree’s new growth will slow down, but you can expect it to grow at a moderate rate for the next few years.

When to Plant Fall Blooming Bulbs?

(Crocus speciosus photograph courtesy of Sonja Keohane, all rights reserved.)

Question:
I just wanted to double-check a question about fall flower blooming. For fall-flowering bulbs like Colchicum autumnale, true hardy crocus varieties, and hardy cyclamen, can one plant now to get fall flowers because the flowers come up on the bulbs so quickly. Is this correct?


Answer:
I would say yes, this is a good time to begin your planning and planting of fall blooming bulbs. You are correct that fall blooming bulbs have a tendency to come up rather quickly, whether they are Colchicum, Crocus, or Cyclamen. The ideal is to plant roughly a month before the expected bloom time. Therefore late July or August is the appropriate time to plant. Some companies and seasoned individuals recommend getting started earlier, and the reason for that is to ensure that you get the bulbs that you want before it is too late. Because the selection of applicable fall blooming bulbs for our area is not as great as that of spring blooming bulbs, growers recommend buying early to make sure that your order is placed, processed, and shipped in a timely fashion. If you end up ordering and getting your bulbs too late you may find that the bulbs have already started to push their blooms before they have had the chance of being planted and establishing new roots. This may lead to a poor first bloom in your garden. To have the best chance of a decent bloom, plant your fall blooming bulbs in early August in well-drained soil and water during periods of drought.

Also, while we are on the topic, remember that most fall blooming bulbs put up their foliage in the spring, completely separately from the flower. The spring foliage is the bulbs chance to photosynthesize and store energy and carbohydrates for the upcoming fall flower. Many people forget where they planted their fall blooming bulbs and when the foliage comes up in spring they cut it back thinking it is some sort of weed. Then when the flowers emerge in fall, with diminished energy reserves, and the flower is less than spectacular people wonder why that is.

Therefore, order your fall blooming bulbs now and get them planted before the middle of August. Water them in times of drought and make sure they are in well-drained soil so that you do not run the risk of rotting the bulbs themselves. Lastly, if you fear you may not remember where they are planted, consider marking or mapping them so that you do not accidentally remove the foliage in spring. Enjoy!

Squirrels eating my tulips in Hoboken, NJ

Question:
I have a garden in Hoboken, NJ, where I have planted a couple stands of tulips. Now that they are coming up, I am noticing squirrels (and/or rabbits) eating the foliage. Is there a way to deter them from eating them all to the ground?

Answer:
This is an issue that I have heard of many times, and the solutions people come up with get more and more creative every year. Here is a list of popular options:

Pepper sprays are used by many, including these two listed in Rodale’s "Great Garden Formulas":
½ oz. Tabasco, 1 pint water, ½ teaspoon dishwashing liquid, 1 teaspoon chili powder
(or)
2 tablespoons cayenne pepper steeped in 1 quart very hot water, mixed with 1 teaspoon horticultural oil

The first recipe is recommended to spray around your tulips, not necessarily on them. The latter is recommended as a foliar spray. As long as the weather stays dry these sprays usually do the trick. One catch is that sprays need to be reapplied after rain storms. The other factor is that some consider this method to be inhumane to the squirrels.

The advice many publications give is to incorporate bulbs in with your tulip planting that squirrels will not eat, namely Narcissus spp. (daffodils) and Allium spp.. There are miniature Narcissus that can be used subtly while not taking away from the show the tulips put on.

If the squirrels are going after the bulbs before they emerge, try planting your bulbs in “bulb cages”. Information about various shapes and sizes are available online. Along those lines, a good recommendation I read once said to lay down a layer of gravel below the soil above where you planted the tulips. The tulips will be able to push through the gravel but the squirrels are usually deterred from digging through the gravel and give up.

My last thought, and certainly the funniest sounding option I have ever heard of is to use petroleum jelly. In all honesty I have never tried this, but other gardener’s accounts I have read claim that it works well. To deter squirrels and rabbits alike, some have written that putting petroleum jelly (Vaseline, etc.) on the foliage of the plants work very well. It does not affect the look of your plants but the coating is enough of a deterrent that the little critters will stay away.

If anyone else has tips that have worked for them, I would love to hear your stories. Feel free to email me at the address above – Thanks!