How late can you plant zinnia seeds?

Answered by Douglas Hiatt

When it comes to planting zinnia seeds, the timing can vary depending on the length of the growing season in your area. If you have a long growing season, you can actually plant zinnias as late as July and still have enough time for them to mature and bloom before the end of the season.

Zinnias typically require 75-90 days from seed to bloom, so a July sowing will give the plants ample time to reach maturity by September. This is particularly beneficial for areas that experience mild winters or don’t freeze, as the zinnias can continue to bloom well into the fall.

However, it’s important to keep in mind that as the days get shorter in late summer and early fall, the blooms on zinnias planted in July or later may be smaller compared to those planted earlier in the season. This is because zinnias rely on longer daylight hours to produce larger, more vibrant flowers.

If you live in an area where the growing season extends into September or even October, you can still plant zinnias as late as August. However, it’s worth noting that the later you plant, the smaller the blooms may be due to the diminishing daylight hours. Nevertheless, zinnias are resilient and can still bring a burst of color to your garden even with smaller blooms.

In my personal experience, I have planted zinnias as late as August in a region with a long growing season. While the blooms were slightly smaller compared to those planted earlier in the season, they still added a beautiful touch to my garden well into the fall. It was a delightful surprise to enjoy the vibrant colors and cheerful presence of zinnias even as the weather started to cool.

To summarize, if you have a long growing season and live in an area that doesn’t freeze, you can plant zinnias as late as July or even August. While the blooms may be smaller as the days get shorter, zinnias can still bring beauty and color to your garden. So don’t hesitate to plant some zinnia seeds even if it’s later in the season – you might be pleasantly surprised by the results!