When to Plant Cut Flowers in Utah

The bipolar weather here in Utah makes it hard to feel confident about planting schedules.

One day it seems as if we are on the verge of spring, the temps are mild, the sun is shining and the birds are singing. The next day it is a white-out blizzard and we are scraping an inch of ice off the car windshields.

This weather messes with my mind and I start second guessing my planting schedule, before firmly reminding myself not to jump the gun.

Knowing when to start planting depends on two things: your frost dates and the hardiness of the plant or crop.

First, Google your first and last frost dates and mark them in your calendar.

Next, you will need to identify if the crop is a cool hardy annual, tender annual or perennial.

Identifying a plant’s hardiness is as simple as giving it a quick Google.

Below you will find my planting schedule for cut flowers. Remember that the planting dates are for direct seeding or planting transplants. If you want to transplant a cool hardy plant in March, then you need to start it indoors about 6 weeks sooner in February.

*Note: Some varieties prefer to be direct seeded into the garden and others do better as transplants. Read up on your specific plant to know which it prefers.

When to Plant Cut Flowers in Utah (based on the Lehi area):

Hardy Annuals:Β 

Cool hardy annuals are the plants that can handle the freeze and shake it off. In fact, many of these plants prefer a long cool establishment period to grow a robust root system and will produce more abundantly as a result.

These cool hardy plants are planted either in the fall (if they overwinter in your zone) or 6-8 weeks before the last spring frost date.

I transplant or directly seed hardy annuals in the fall 6 weeks before my first frost date. For Lehi that is around October 26th, so I plant mid September. If I miss that window (or want to plant a succession crop to extend the harvest) then I plant 6-8 weeks before my last frost date. My last frost is around April 22nd so I aim to plant around mid to late March. Below are some of the hardy annuals I plant at these times in my zone 7 climate:

Snapdragons

Icelandic Poppies

Orlaya

Bupluerum

Foxglove

Bee Balm

Delphinium

Larkspur

Queen Anne’s Lace

Honeywort

Pincushion

Stock (late winter planting only)

*Note: Flower Farmers also plant annual bulbs/corms in the fall (these cannot be planted in late winter unless you buy pre-chilled bulbs), such as tulips or ranunculus (in my zone ranuncs need overwintering protection in a low tunnel). Certain perennials also do best planted in the fall such as peonies or daffodils.

Tender Annuals:

Tender annual plants will not tolerate a freeze and must be planted after the danger of frost has passed.

I transplant or directly seed my tender annuals around Mothers’ Day (mid May), just to be safe. Most of these can continue to be planted in successions throughout about mid July (to know for sure, you must look at the “days to maturity” on the seed packet and count back that number from your first fall frost date). Below are some of the tender annuals I plant in my zone 7 climate:

Sunflowers

Zinnias

Amaranth

Cosmos

Dahlias

Ornamental Grasses (bunny tails, frosted explosion etc.)

*Note: Dahlias are a tuber crop that are planted at the same time as the tender annuals because they do not tolerate a freeze in my zone. In milder regions, the can be overwintered.

Perennials:

Perennials are pretty simple. You plant them when the ground is not frozen. However, certain perennials like peonies or daffodils perform best when fall planted.

I hope you noticed that most cut flowers are actually planted as hardy annuals in the fall. I like to call fall the “second spring” for most of Utah.

Mastering hardy annuals in the fall is key to an abundant spring cut flower harvest in Utah!

Of course, some growers have taken it a step further and use season extension devices to plant at earlier times. I use a low tunnel (think mini greenhouse) to overwinter ranunculus and anemones.

I also use frost cloth tunnels to plant some of the semi-hardy annuals under (these are hardy annuals that just need a smidgen of winter protection to perform better come spring).

If you are interested in companion planting fruits/vegetables then I recommend looking at this planting guide.Β (That guide also touches on micro climates to consider.)

For cool hardy plants specifically, I recommend reading Lisa Ziegler’s book Cool Flowers.

If this guide was useful to you then please leave me a comment below and share! I would love to hear from you!Β