Cut Flower Updates: October 10, 2025

This will be our final weekly update of the growing season. If you have a minute, we'd appreciate it if you shared your feedback on this resource by filling out this short (3-5 minute) survey! 

While many operations continue harvesting and selling well into the fall, as the majority of production shifts indoors or under high tunnels, outdoor production is slowing down at a fast clip. However, that doesn’t mean that field tasks are complete! Fall can be a great time for planting new perennial beds, woody plants for future cut stems, and of course, bulbs for next spring. In this final installment of the weekly cut flower updates, we'll zero in on the basics of tulip bulb planting to ensure a healthy crop for next spring.

Many Pennsylvania growers I've spoken to have expressed interest in shifting at least some of their production towards the shoulder seasons of early spring and late fall. In addition to avoiding the heat of midsummer labor, there are generally numerous opportunities to offload fresh stems to flower-hungry customers during the "off-season." Planting hardy bulbs in the fall allows for an early harvest for spring markets.

Tulips, like other plants grown from bulbs, are prone to pathogens, particularly in poorly drained soil, shady areas, and areas with poor air circulation. Diseases affecting tulips include Botrytis tulipae (also known as tulip fire), bulb rot caused by Fusarium, blue mold generated by Penicillium sp., Pythium root rot, and bacterial soft rot caused by Erwinia sp. Avoiding disease issues starts well before planting.

Bulbs should be purchased from a reputable dealer and inspected prior to planting. Some disease issues, namely Penicillium and Fusarium, can impact bulbs in storage, and will be visible as bluish or white-pink moldy growth, respectively, on the bulb scales. Some growers use fungicide dusts or dips as pre-plant treatments to control existing fungi and protect against new infection, or purchase fungicide-treated bulbs. Active ingredients in synthetic fungicides may include thiabendazole or thiram, while organic options include products with the bacteria Bacillus subtilis and Streptomyces lydicus. Avoid planting bulbs that are mushy, damaged, or display visible infection, and avoid planting in a bed in which diseased tulips were present within the last 3 years.

For field-grown tulips, there are a few different planting methods to consider. One is to use a bulb planter or auger to create individual planting holes in the soil for each bulb. A more popular strategy among commercial growers is to dig a trench and plant all the bulbs at once. This typically involves cultivating the soil to a depth of 10-12 inches, shoveling the loosened soil aside, and placing the bulbs on the bottom of the trench (at about the same spacing as eggs in a carton, with the growth point facing upward) so that when the soil is returned, the bulbs are about 6-8 inches below the soil surface. 

Finally, avoiding soil disturbance entirely, some growers create temporary beds on top of their existing planting beds. The bulbs are "planted" on top of the soil surface (again, at egg carton spacing) and covered with 6-8 inches of aged compost, which is held in place with wooden boards and rebar stakes.

Once planted, water the bed well. Depending on the level of pest pressure at your farm, you may find it necessary to further protect your planted bulbs with netting or a similar barrier to deter hungry mammals from excavating them this fall and winter.

That's a wrap on this season's weekly cut flower updates! We'll continue to post once a month through the fall and winter, and we'll be back with regular updates this spring, along with other educational opportunities. If you've found this resource helpful, and/or have suggestions for next year, please take a moment to fill out this survey. You can also email Margaret Pickoff at mfp5667@psu.edu. Your feedback means so much.