Last week we received a shipment of over 23,000 lily bulbs. Almost 60 crates! It sort of takes the wind out of you to look at two pallets of bulb crates and know that they all have to go into the ground in the next three weeks. Ugh! To make matters worse, rain was coming, and we had to get the first half planted right away. Thankfully, we have two women working for us this winter, and we set to planting. Standing in front of a quarter-acre section of beds, Frank started saying he wanted some varieties planted where they would get morning shade, and some where they would get afternoon shade, and some in the center of the shade all day long. Susan, who had just started with us the week before, looked puzzled. “Ah...I have a question.” she said. “What shade are you talking about?” As it happened, we were standing in the middle of an open, sunny field - not even any little trees around. “The shade house that we are going to build here, of course,” Frank said. “Can’t you see it?” It never occurred to him that although this shade house already existed in his mind, and it was as plain as day where the morning sun would fall, nobody else could see it. But we went ahead and planted the lilies anyway, just as if it were there.
We have a bad habit of planting greenhouse crops where no greenhouse yet exists. Several years ago we first experimented with lilies, and planted several thousand where we were going to build a new cold frame. The cold frame didn’t get built that spring, but the lilies did fine anyway, and we learned by default that we could raise field-grown lilies here in Texas. Who would have guessed. This year our greenhouse crop without a greenhouse is tulips.
At least this year the greenhouse frame is there. The entire greenhouse was there last summer, all shiny and new. We built a new, 144 foot long, 20 foot wide cold frame. The plastic hadn’t been on more than a month when a Texas dust devil tore it off, leaving the bright new frame shining in the sun and $600 worth of plastic flying off into a clear blue sky!
But we planted the tulips anyway. Two 144-foot beds in the ground, and about 100 bulb crates. Bulb crates are those heavy, black plastic crates that the bulbs are shipped in. Many growers fill them with soil and grow the crops in those crates, but of course when you get 500 bulbs in a crate, you need more than the original crate to plant them in. We found that a good source for empty crates are big greenhouse companies that grow potted crops for the florist trade. These companies typically grow crops such as Easter lilies, tulips, daffodils and hyacinths in 6 inch pots for holiday sales. They don’t usually have a use for the big black crates. They are bulky and hard to store, and actually become a disposal problem for some companies. We called a local greenhouse and they were glad to let us come and get as many as we could haul off. They even helped us load them! We made three trips, and picked up several hundred crates. Even if you had to pay a nominal charge, maybe a buck a piece, they are worth it. They will last a long time.
We ordered tulip bulbs for forcing. What "forcing" means is that the bulbs are chilled down artificially and forced to grow out of their normal season, as opposed to planting the bulbs in the fall in field beds and letting them bloom naturally in the spring. Forcing bulbs are prepared by chilling the bulbs for a set period of time (up to 16 weeks) before bringing them into the greenhouse to grow. Many spring bulbs such as tulips, iris, hyacinths and daffodils need this cooling period to produce high-quality flowers. It varies per crop, but every type has its minimum requirement. A typical symptom of insufficient chilling is short stems. This is particularly apparent in hyacinths. More chilling = longer stems.
There are two ways, or programs, to chill tulip bulbs for greenhouse cut production. They are called the 5 degree program, and the 9 degree program. This refers to the temperature, in Celsius, that the bulbs are stored at when being chilled. The biggest difference is that 9 degree tulips are planted in the pot or crate, and chilled for a long period. The bulbs root in the container, and once they are brought into the greenhouse, they grow rapidly. The chilling period can take up to 16 weeks, depending on the variety, but then the crops blooms in as little as three weeks after being brought into the greenhouse. This method is most often used by growers who grow potted bulbs for the holidays. (The guys you’ll go ask for crates from!)
How to chill
Growing tulips in a 9 degree program results in fast greenhouse crops, but it takes up a lot of space in the cooler. Frank once worked at a big greenhouse range that used a refrigerated tractor trailer just to chill their Valentine’s Day and Easter tulip crop!
We used bulbs chilled in the 5 degree program. With this program, the bulb supplier chills the bulbs dry, and the grower plants them upon receipt. The bulbs are stored loose in the crates for 8 or 9 weeks at 5 degrees, and then after planting the grower grows them for an additional 8 to 10 weeks. The overall production time is about the same, but the key here is that the cut flower grower can plant pre-chilled bulbs in ground beds, and bypass chilling the bulbs onsite. The cost for 5 degree bulbs is not significantly different.
The most important requirement for growing 5 degree tulips, however, is that the crop be grown cool. Essentially, the chilling process continues as the plants slowly grow. The soil temperature in the growing beds or crates needs to be between 50-55 degrees Fahrenheit. That can sometimes be a problem here in Texas, and it limits how early we can plant the bulbs. Temperatures warmer than than 55 degrees can cause the plants to bloom too short.
Because the bulbs arrive pre-chilled and should be planted immediately, we scheduled our bulbs to arrive in three shipments, two weeks apart. This staggers out the bloom time on the other end. If we were really big-time tulip growers we would probably get weekly shipments, but this was still an experiment, so to speak. (Ha! A 15,000-bulb experiment!) We received our first shipment in late November. Before then our temperatures here in the south are too warm.
We planted most of our bulbs in ground beds under the soon-to-be-covered greenhouse. The bulbs should be planted as deep as possible, but they can be planted very close. We have less than 2 inches of space between the bulbs in all directions. The beds were fertilized with turkey-litter compost and a concentrated bat-guano fertilizer. The greenhouse remained uncovered, and the bulbs sprouted and have survived several freezes into the 20s. They are certainly being grown cool!
We also potted up some bulbs into bulb crates. A standard bulb crate is about 16 inches wide and 21 inches long. They can range in depth from 4 inches deep to about 8 inches deep, depending on what was originally shipped in them. We used crates that would hold at least 6 inches of soil. 3 inches of soil was put into the crates, then we gently pushed the bulbs into this soil and covered them with 3 more inches of soil.
Sometimes the bulbs can push themselves out of the soil as the roots grow if the soil is light, and it has been suggested that some sand be placed on the top of the soil in the crates to hold the bulbs down. We used a “Peat-lite” soil-less mix, with no sand on top, but we had no trouble with the bulbs pushing up.
We have been fertilizing our greenhouse tulips with a standard, non-organic water soluble fertilizer (the blue stuff!) along with an occasional application of calcium nitrate. Calcium is an important nutrient in tulips because it helps build strong stems (Just like Wonder bread--strong minds and bodies!) and overcome a problem known as “stem-topple” that can occur when the stems grow too long and weak and fall over before harvest. In our bright light conditions here in the South this is less of a problem than in more cloudy, darker regions. We don’t worry about Calcium in our ground beds because our soil is limestone based. We’d like to get rid of some of the calcium!
We haven’t had to use any fungicides or pesticides on our tulips, but because we grow them so close together, good airflow in the greenhouse is essential (The greenhouse with no plastic has no trouble!) Good airflow is the key to success in any greenhouse crop. Even if you can’t open up your greenhouse because it is too cold outside, a regular, cheap window fan can move a lot of air around in a greenhouse. We hang them from the crossbars of the greenhouse. Our Ball Seed rep, Michael Henzler, told us that as little as 2 miles per hour air flow is enough to prevent spore germination in botrytis.
Our tulips in the crates are just starting to color up as we write this, so we haven’t picked any yet, but we have a tulip picking expert working here for a few weeks this winter. Susan Corrigan worked for a spell at Ed Pincus’ Third Branch Flower Farm in Vermont where she says she “picked white tulips for an entire month! They grew about 125,000 tulips there, and I probably picked 20% of them!” Susan says they picked them tight, for shipping, just when they started to show color. Sometime on warm days, they had to be picked twice or even three times in a day as they would color up. Susan says they would harvest the stems by pulling firmly up at the base of the stem. “You have to grab it way down and pull or the stem will snap off at the ground level and be too short” she says. Ideally the stem would snap off underground and leave the bulb in the ground. Sometimes the bulb would come up with the stem. Susan says she would hold the bulb between her knees and pop the stem off so she could do it one handed! They picked into plain water, and once picked, they could store the stems in a cooler for many days.
Third Branch grew a lot of “French” tulips, which are varieties that are typically late growing, but have very long stems and large flowers. We are growing Triumph tulips in the greenhouse ground beds and in crates. They are not as tall, but a little earlier. They come in a wide range of colors. Most bulb suppliers probably have a 5 degree tulip program. Two sources that we know of are Bulbmark (800-868-0426) and Gloeckner. (800-345-3787). You need to order you bulbs in the summer to allow time for the companies to chill the bulbs.
Lilies in crates
We also grew some lilies in bulb crates this winter. As we said before, we grew our original crop of “greenhouse” lilies outdoors where the greenhouse would be built, but we finally have some under cover. We are growing them in the cool house (50-55 degrees) where we are growing the tulips, and they look great. We are growing asiatic lilies, orientals and LA hybrids. LA hybrids are a cross between asiatic and longiflorum (Easter lily) types. All three look good, but the LA hybrids look great! One particular standout is a variety called Manhattan. It is a deep shell pink, with very dark green leaves. The buds swell up like an Easter lily and the flowers are huge. We’ll be looking into more of these LA hybrids in the future.
We planted the lilies in the deepest bulb crates we could find. Lilies have roots at the bottom of the bulb when you plant them, but those are just anchor roots. The real roots that sustain the plant grow out of the base of the new shoot, just above the bulb. Therefore it is very important that the bulbs are planted deep enough. You need at least 3 inches of soil over the bulb--more is even better. A lily that can’t make a good root system above the bulb will literally starve to death.
Lily bulbs need to be pre-chilled like tulips. Your bulb supplier will chill them for you. Lily bulbs can be held in frozen storage for up to a year, so if you place your orders right, you could have bulbs growing year-round. We planted 20 lily bulbs to a crate. Ron Beck, Gloeckner’s lily guy, told us we could plant 16 to 20 bulbs per crate, depending on bulb size and light intensity. We have high light here in Texas, so we planted 20 per crate, but if you get a lot of cloudy weather you will want to plant less.
Again, air flow if important in disease control. You’ll want more space in the crate in darker, damper climates. Most of the lilies haven’t had to be treated with any pesticides, but the orientals are more susceptible to the deadly botrytis, and it has been showing up on the leaves that are up close to the buds. We are also starting to see a few aphids on the orientals. Looks like we’ll be dropping them from the program next season!
There are many lily suppliers in the U.S. The two companies above carry lilies. To grow lilies in the winter it is best to book your bulbs well in advance. They will be put in storage for you. For the field crop, we use the new year’s bulb crop which is ready in January.
Well, we are glad to say that we finally got the last tulip greenhouse covered again. Two things pushed us into it. The first is that we are finally taking a vacation to Mexico, and on the day before we are leaving, instead of packing, we are out before dawn pulling greenhouse plastic! The other thing is that a full blown Texas Blue Norther is barreling down our way, and by the time we leave, it will be dropping into the teens. Ugh! Why does that always happen when you leave? That is really what got us to finally cover the tulips! We asked Susan several times today “Why do we do this!?”
“It’s a passion” she said. “It’s a passion.”