Season Wrap-Up: Turn Spring Insights Into Next Year's Success

With the Memorial Day holiday now behind us, the 2026 spring season is just about history. Hopefully it was a great spring for all of you, and you were able to enjoy the beautiful weather every weekend. You may still be running specials and/or combining remaining plants into creative, mixed containers to help sell down on what’s left. Or you may have already closed for the season. Now, with all the new and exciting plant materials, the trend for larger container sizes and a renewed interest in gardening, spring sales can often continue well into summer.

Regardless of where you currently find yourself in the spring season, now is a key time to make detailed notes on how this past season went. While memory is still fresh, your notes will be of more value to you when planning for the next season. For the best results, try and review the past season as soon as possible.

Some helpful questions to ask when reflecting on the past season; What sold well and what didn’t? What were customers requesting that you didn’t have? What colors were most popular or requested? Be cautious when making color changes as these trends seem to be more volatile than others. There is often no rhyme or reason to what makes a color popular at a given time, it just happens.

Note what didn’t grow well. Perhaps you found out why a particular crop struggled… but maybe not. We all have those plants that we struggle to grow well. If you constantly have issues growing something to your standards, it might be best to just let it go and focus on what you do grow well. An example might be caladiums. Many growers struggle with caladiums due to their need for root zone heat. Without it, they can be very slow to grow to a decent size until the summer heat hits.

Also note this season’s weather as well and anything else that occurred that may have helped or hindered sales. Keep in mind that next year’s weather will be anything other than what this year’s was. Work it into the equation, but don’t make any rash decisions based on how good or bad the weather was this season.

These notes will be important to help you plan your next season. But they also need to be acted on with some restraint, as the only true constant in this industry is that no two consecutive springs are the same. Hesitate to make any drastic cropping changes unless you feel absolutely certain that such a change is warranted.

More questions you’ll want to ask yourself; how many of the following did you order for last season:

• Potting soil (bag size and type)
• Fertilizer (per formulation)
• Hanging Baskets
• Other containers/trays (each type)
• Inserts/trays (each type)

We’ve had quite a few calls this spring regarding aphid infestations that seemed to appear overnight. Aphids are nasty. They come in all colors, reproduce exponentially, and can be difficult to control, especially if their presence is not detected early. And to add insult to injury, they leave behind, even after successful chemical treatment, their husks and sticky, honeydew secretions.

To get the upper hand on these and other common spring pests, such as thrips and whiteflies, try to detect these pests when populations are low. This can be as simple as walking your benches twice a week taking a close look at each crop for early signs of insect presence. Aphids seem to gravitate towards ipomoea, calibrachoa and peppers before anything else so watch these especially. Aphids are also larger and easy to spot, so if an effort is made to catch populations early, this is one of the easiest pests to control.

Whiteflies are not quite as common but can often find their way into greenhouses via existing populations that spent their winter on weeds and pet plants, as well as piggybacking into the greenhouse on incoming plant material. Yellow sticky cards, in addition to weekly inspections, especially under leaves, will go far in detecting these pests.

Thrips are a bit more challenging. Fortunately, they seem to be a bit less problematic in recent years. Yellow or blue sticky cards are the best way to monitor. Some say that blue cards are best at attracting thrips, but my experience has been that yellow works better, also attracts other pests, and are easier to monitor.

Once you find these pests, act quickly. Depending on the infestation, that may mean spot-spraying the affected areas or treating the entire crop, or even the whole greenhouse. If you discover small populations late in the crop, spot treatments are usually enough because the risk of further damage is lower, and shipped plants will be exposed to sun, wind, and natural predators.

Another issue this season was fertilizer rates and not knowing just how much to feed. Be sure to use a commercial fertilizer (not Miracle Grow!) when growing annuals. Base your rate off the mixing instructions on the front of the bag. If using an injector with a 100:1 ratio, use the ounces per gallon of concentrate rate for the ppm that you’re wanting to use. For annuals, I like a constant liquid feed (CLF) of 250 ppm Nitrogen (N). You can fertilize a bit more or less, but please be consistent. Annuals grow fast and need adequate fertilizer to do their best.

To measure the ppm of your fertilizer water, you can use an electrical conductivity (EC) meter. EC is the measurement of dissolved salts in your water. Begin by measuring the electrical conductivity (EC) of your water before it goes through the injector. Then subtract that reading from the EC of your fertilizer water as it comes out of the hose or drip tube. That measurement gives you the actual EC from your fertilizer alone. This reading can then be compared to the EC value on the front of your fertilizer bag. For example, if you’re using JR Peters 20-10-20 and your net EC reading (after subtracting the raw water reading) is 1.3, you’re feeding at about 200 ppm Nitrogen.

Shifting into mum season.

Most have received your mums or will be soon.

Key points:

• Plant as soon as possible upon arrival. Try to have pots waiting and plant immediately. Water them in with a high nitrogen fertilizer and continue to fertilize with each watering. Most of today’s mums require no pinch but to get that well-rounded shape and desired size, you must fertilize often. Your crop’s success leans heavily on a good feeding program. 250 to 300 ppm each watering for the first month is perfect. Use a 20-10-20 or similar, nitrate-based fertilizer. This promotes lush growth, lateral branching, and food reserves to encourage lateral branching, good size and that desired, spherical shape. Around the end of July, you can transition to a mum finisher such as JR Peters 22-5-16 that has low phosphorus (tones growth) and chelated iron that makes itself immediately available to the plants, even at a higher soil pH.

• Keep warm during May and early June when colder nights can be a concern. Temperatures below 65F for several consecutive nights can prematurely initiate buds which can then stop foliar growth. The common term in the industry for this phenomenon is crown budding. Mums initiate flowers with the shortening of days which naturally occurs around July 25. But they also initiate flowers when exposed to several consecutive, cool nights in the low 60’s. This crown budding shows up later in early summer and can be very frustrating to the grower. So, if nights are a bit cool, it would be best to keep your mums in the greenhouse for a few weeks until summer temperatures finally arrive.

• Always try to grow this crop outside. Never let them dry to the point of wilting as stress on this crop often results in weak branching and breakage at the end of the crop. Be sure to watch for caterpillars and aphids. These can sneak up on you during the summer months.

Questionsor Concerns?
If you need help or elaboration on any of the above topics, please feel free to contact us. If you need a source for or advice on annuals, perennials, pH or EC meters, soil or anything else, we can help you with that as well!