Frequently Asked Questions
Students' Questions and Experts' Answers
Contributed by Tulip Expert
Bud Markhart
Ways to use in the Classroom

Special thanks to Professor Bud Markhart for providing his time and expertise to respond to your tulip garden questions. This page contains questions and answers from 2011.

Dear Students,
What great questions this year!  I hope my answers help and that you learned a lot from watching your tulips grow!  Great science begins with careful observation followed by great questions.  These questions show me you are on your way to being great scientists! -Dr. Markhart

Teachers: You can use today's Answers from the Expert, along with those from previous years, in these activities suggested in "Learning from Experts".

Bud Markhart

From: Texas
Frassati Academy

Why is the pollen on the anthers purple? We are leaning in Botany about the pollens that different insects prefer. What insect does the purple pollen of the tulip attract?

A: Pollen color depends on lots of things.  In plants that have been developed by plant breeding, humans have selected the color of the pollen.  The purple pollen was part of selecting for the deep red color of the petals.  We should also remember that bees, the main pollinator of tulips, see color differently than we do.  They see mostly ultraviolet light which is light that we do not see. Therefore the “color” of the pollen to a bee is different than the “color” of the pollen to humans.

Q: Do bigger bulbs grow bigger tulips or does the size of the bulb not matter?

A: Yes, bigger bulbs will produce bigger plants.  After the flower finishes in early summer the tulip leaves photosynthesize and store as much energy as they can in the bulbs.  This energy is used to grow leaves and the flower next spring.  The bigger bulbs have more stored energy and can therefore produce bigger plants.

Q: What should we do now to help our tulips grow back next year?

A: After the flower is done, cut the flower off and treat the plant kindly.  For the tulip to flower next year it needs to store a lot of energy in the bulb during the summer.  Therefore the plants needs just the right amount of water, fertilizer, and sun.  The best rule of thumb, green thumb that is, is not too much, not too little. I’m sure your teachers can find specific information on what is just right for the tulips.  One thing you can start doing right now is to weed around the tulips.  Weeds will use light, water, and nutrients that you would rather have helping the tulip to grow.

From: Missouri
Valley Park Elementary

Our tulips were just ready to bloom when we got five inches of snow and a hard freeze. Will they survive?

A:  Snow is usually not a problem for tulips.  I have seen tulip buds covered in snow and open wonderfully.  More is the hard freeze.  So much depends on how fast the tulip was growing, how open the bud was, and how cold it got.  A hard freeze on an open flower will often kill the flower, but not the plant.  Keep it watered and fertilized and weeded and it should come back next year!

From: South Carolina
Hammond Elementary

Q. We planted 80 tulip bulbs here at Hammond Lower School in Columbia, SC. We have 5 twin blooms. Is this normal? Thanks!

A: Cool, twin blooms are not very common.  Usually this happens when two bulbs are stuck together when they are planted.  Two flowers from one bulb is very rare. You’re very lucky!

From: Iowa
South O'Brien Schools

Q: What animals use Tulips as a food source?

A: There are lots of critters that eat tulip flowers.  Chipmunks, squirrels, rabbits, deer, prairie dogs.  Most often they will eat the flower buds and leave the leaves.  Very frustrating!

Q: On average, how tall does a fully bloomed tulip grow?

A: The height of the tulip bloom depends on two main factors. The first is the variety of tulip.  Tulips vary in height from 4 inches to 24 inches, two feet! That is one tall tulip.  The other factor is the environment during the spring. Depending on how warm it gets the flower stems can vary a lot in height.

Q: What is the wax on the tulip's leaves made of?

A: The wax on the tulip leaf is called the cuticle.  The wax is very similar to wax that you might put on furniture or that you see in bee hives. The wax is made of really big molecules of carbon and hydrogen.  The wax on the surface is really important because it keeps the leaves from losing too much water.  Just like wrapping a sandwich in wax paper to keep it fresh.  The other cool thing about tulip leaves is the top layer of the leaf, the epidermis, which has the waxy coating, peels off really easy. If you have a microscope in the school you will be amazed at what you see if you look at a piece of the leaf epidermis!

From: West Virginia
Hurricane High School

Q: We have only 40 tulips out of about 300 come up. We have clay soil, planted on a slight angle, and followed all other directions (8 inches). What went wrong? And, why aren't Emporer tulips taller? My husband said they were Napoleonic in stature.

A: Tulips do not like clay say.  If the soil got wet and stayed wet the bulbs could have drowned.  Eight inches is deep in clay soil.  You can dig down and see if the bulbs rotted in the soil. Another possibility is that the soil got really hard on top of the bulb. The shoots could have tried to push to the surface and could not make it.  That is probably whey the ones that did make are so short. They used up a lot of energy getting to the surface of the soil.  Next year add sand and organic matter to the soil and do not plant so deeply. 

From: Connecticut
Eastford Elementary School

Q: Grade 3 students did a "walk around" the school to see if any plant growth was evident after a tough winter. After peeling back the leaf mulch over just a few bulbs in the test garden, we discovered that tulips had indeed emerged: leaf tips were above ground level by approximately 3/4 inch! We did not re-cover the emerged tulips. We will be comparing rates of growth between the covered and uncovered tulips. In the comparison planting area that we refer to as our "wrong" garden, where bulbs are planted at a variety of incorrect depths, and the garden itself is placed near a foundation and facing east, we found one tulip grown up to a height of 4 inches. That bulb had been planted just under the soil surface! What combination of factors affected its growth so that it was taller than the "correctly" planted bulbs in the test garden? The "wrong" bulb didn't even have mulch! Can an expert shed some light on this? Thank you! Ms. Joan Muller

A: You got lucky!  One reason for planting the bulbs more deeply is so they do not freeze during the winter.  If the winter is mild and soil warms quickly, then the bulbs not mulched and planted near the surface will start to grow early. They will be ahead of those planted more deeply in the cooler soil.  Hope you are lucky next year, too!

From: North Carolina
Clear Creek Elementary School

Q: What is the little yellow star shaped part in the middle of the close up of the tulip in picture #3? What are the purple things called?

A: I don’t have the picture, but I think what you are describing is the “stigma” of the flower.  This is the part of the flower where pollen land or are deposited by bees. The pollen germinate and a tube grows down to the base of the flower where it fertilizes an egg to produce a seed with a baby tulip plant inside.  The purple things are the “anthers”.  They produce the pollen.

Q: Can tulips be different colors? What makes a tulip decide what color it is going to be?

A: Tulips come in lots and lots and lots of colors.  This is part of the reason they are so popular.  The genes in the tulip plant determine what color the flower will be.  In tulips it is all genetics.

Yomitan, Okinawa, Japan
Okinawa Christian School International

Q: Our school is in Okinawa, JAPAN. We had a really hard time buying the Red Emperor tulips, but got them in time in November to refrigerate them for 6 weeks and plant them the first week of January. Our first blooms were in February, but every plant that bloomed had shriveled petals before the flower was fully open. Many did not bloom at all. The leaves still look healthy, but all blooms have been gone for weeks. What should we do differently next year?

A: What caused the flowers to be so poorly formed is hard to say.  Most likely something happened during shipping or storage.  Too dry or too cold could cause damage.  If the leaves are growing well then they might bloom beautifully next year.  Remember you will need to start with new bulbs for Journey North Test Garden next year.  I hope you will be able to find your bulbs for the experiment earlier next year.

From: Minnesota

Q: Why do the tulips we planted 2 years ago in the fall emerge before the tulips we planted last year? The older ones always seem to come up earlier!

A: That is an interesting question and I do not know the exact answer.  I can, however, give you some educated guesses. 

  • The older bulbs may not be as deep in the ground as the new bulbs.  Some bulbs change depth as they grow and the older ones may be nearer the surface.  You can dig some up from both groups and look to see if this is the case. 
  • Another possibility is that new bulbs were gown in a much warmer environment than Minnesota and this warmer environment may leave information in the bulb that it has to warm up to a certain temperature before it starts to grow. Whereas, tulips that grew a whole year in MN, will have information stored in the bulb that they can start to grow when it is colder.  Hmmmmm. I like the second explanation better than the first.

Tulip Expert, Bud Markhart
Professor, Horticultural Science