As our 2023 Dahlia tubers growing season comes to a close and we look over the garden to see some of the season’s last blooms starting to open while others drop their petals, we reflect on things we have learned this year. As with any growing season, there are many things to learn and take away to improve the next season.

What did we learn this year from growing Dahlia tubers?

In our first year of growing Dahlias tubers on a large scale both at the urban farm and the Ramona farm, we conducted several experiments to answer common questions that growers of Zone 9 and 10 ask. Here is what we found out.

Q: When can I plant Dahlias tubers in Zones 9 and 10?

A: We started planting our Dahlias in late May, with the first blooms blessing our gardens in late June. At our San Diego garden and Ramona farm, we have blooms continuously from June until late August and September.

Q: Can I grow Dahlias tubers in a hot area?

A: YES! Our Dahlias did great even in the 100+ degree heat of Ramona.

Q: How often should I water my Dahlia tubers?

A: Although it is hard to give an exact answer to this question as so many different conditions exist that influence watering patterns, we were surprised at how little we needed to water our Dahlias. In Ramona, California, where the summers are very hot and dry, we watered our in-ground planted Dahlias once a week. We actually lost some tubers to overwatering at the beginning of the season before noticing we needed to cut back the watering frequency. In our San Diego garden, where we planted in large 20-gallon pots, we watered only once a week during the warm summer days and twice a week during the hottest spells. Remember that containers dry out quicker than in-ground plantings.

Q: Can I plant broken Dahlia tubers, and will they yield plants?

A: We tested Dahlia bulbs of all shapes, sizes, and conditions and found that planting Dahlia bulbs that were already sprouted or had some broken tubers or damaged parts still yielded happy, healthy plants.

Q: How can I get the most blooms from my Dahlia tubers?

A: We tested the pinching technique and found that those pinched plants produced 2–3x more blooms. We also noticed that “live-headed” plants (meaning we regularly harvested) gave us many more blooms.

Overall, we discovered Dahlias are a durable, drought-tolerant flower that is so easy to grow!