Skip to Content Skip to Navigation

Seasonal Outdoor Growing

Finishing plants outdoors when temperatures are just above freezing can help production in many ways. By increasing your production space and moving more mature crops outside, you can increase the spacing on the remaining plants or order in new plants to get more out of every season. Finishing outdoors under cool temperatures also helps acclimate plants to the outdoor environment, making them tougher, more compact, and increases the plants’ survival rates for your customers when they transplant them. The cool temperatures will slow the crops, so plan for that, but the benefits usually outweigh the longer crop times.

Why grow outdoors? To maximize space, turns and sales
Whether you are a large or small grower, the same challenge always seems to arise: what to do when you’re out of space. The real question is, are you out of space or just out of greenhouse space? Many growers plan production based on the amount of greenhouse space they may have under cover. However, in many cases there may be some valuable outdoor growing space that can be taken advantage of that isn’t currently being used. With a quick leveling of the grade and some weed mat, you may open your options to an increase in profits for the upcoming season.

Many finished product growers utilize outdoor spaces, allowing them to produce more plants through the season and increase their profits. The demand for spring product is certainly there, and increasing profits directly correlates with how many times you can turn product within the space you have. Nothing beats natural light and the cost savings (no fans, electricity, etc.) of growing outdoors on weed mats with a simple watering system.

Watch the Weather
Here are some points which will aid you in being successful in growing plants outdoors in early spring.

  • Before plants are moved outside, they should be acclimated to colder temperatures using holding temperatures.
  • Watch the weather before you begin moving plants outside. Since day #1 and the following few days are critical to the process of hardening off crops, you’ll want to start when the weather will be mild for the first 5-10 days the plants will be outdoors. Optimum conditions include moderate temperatures (40s), overcast skies, and most importantly, little to no wind. Wind dries the plants out and strips away any warm air surrounding them, so avoid windy conditions if possible.
  • We recommend moving plants outdoors approximately 4 weeks before the last frost-free date for your area. Due to fluctuations in weather conditions, the schedule may have to be adjusted. Please note your specific region’s requirements.
  • NOTE: ALWAYS trial outdoor finishing with a small number of plants and expand the numbers as you gain experience.

Moving Plants Outdoors

  1. Group A – Frost 32°F to 25°F

These plants can be placed outside the earliest. When temperatures are not forecasted to drop below freezing for the next 10 days, you should be able to move these plants outdoors. Should the temperature be forecasted to drop below 28°F, protection measures should be taken.

Argyranthemum - all varieties

Bright Lights® Osteospermum

Supertunia® /Surfinia® Petunia (except Mini Strawberry Pink Vein and Mini Rose Vein)

  1. Group B - Frost 32°F to 28°F

This is the second wave of plant material to move outside. These plants can be moved out when odds are good that temperatures are much less likely to drop below freezing. Protection measures should be taken for this group when temperatures are forecasted to reach 32°F. Average daily temperatures should be higher than when group A material was moved out. Generally, a few weeks after group A is moved out, group B can be moved outside.

Goldilocks Rocks® and Campfire® Flame Bidens

Superbells® Calibrachoa

Flying Colors® Diascia

Innocence® Nemesia

Intensia® Phlox

Almost all Proven Winners® perennials & ColorChoice® shrubs

  1. Group C - Frost 32°F

This is the third wave of plant material to move outside. These plants can be moved outside when temperatures are no longer likely to reach freezing. A hard frost will cause damage to this group. If a hard frost is forecasted, protection measures should be implemented.

Sundaze® Bracteantha

Laguna & Lucia® Lobelia

Sunsatia® Nemesia

Superbena® and Tukana® Verbena

This information is available when searching through our culture recommendations.

NOTE: There are always exceptions, and some cultivars are more or less temperature sensitive than others. In the Supertunia® collection, Supertunia® Mini Strawberry Pink Veined, Mini Rose Veined and Limoncello are more sensitive to wind and cold, so they should be moved outside when temperatures are closer to 40°F.

Watering and Fertilizing
Water as necessary. When plants are ready, water thoroughly at a high feed rate. After heavy rains, feed with at least 300ppm of 20-10-20 and then allow the plants to dry out before the next watering.

Cold temperatures slow crops down. Plan for it
Those plants finished outdoors will need additional time to finish. Specific finishing times are difficult to predict due to variability in weather patterns. Outdoor mum production areas are perfect to use as spring cold temperature finishing spaces. It is generally too cold for insects and diseases to prosper in early spring. You should continue to scout for problems, but chemical control measures probably won’t be necessary. Plant growth regulators will also not be needed to control growth in cold temperatures.

Don’t end your season with spring-grown crops
Once the danger of frost has passed, you can safely move all your Proven Winners and Proven Selections crops outdoors. Then, keep growing for summer and fall by starting up heat and drought tolerant crops. These types of crops are in demand from both consumers and growers, and the best part is they're perfectly suited for growing outdoors.

Back to Top

Find plants you love and create idea boards for all your projects.

To create an idea board, sign in or create an account.