How To Pot Up Dahlias To Get A Head Start

You can have dahlias blooming in your garden in August, even here in zone 5. Choose option #1 (do it yourself), or option #2 (don’t do it yourself).

Mike’s do-it-yourself option

If you followed the instructions in You Want Me to Plant My Dahlias NOW?, you are prepared for the task. You’ve got your dahlia tuber. You’ve got a pot. You’ve got soilless potting mix. You’ve got light.

For those of you who have grown seeds indoors, the challenge is minor. The results are what is huge … dahlias from August to October! Dahlias like Spike, who you see pictured here. If you are not so ambitious, see Carol’s not so-do-it-yourself option further below.

Mike says

Pick a pot that is large enough to accommodate the tuber. Use a soilless potting mix rather than actual garden soil. Garden soil has the possibility of harboring insect pests that might be detrimental to the early growth of your tuber’s roots. Plant the tuber, allowing just the top of the tuber above the soil line. This will allow you to watch the sprout development. It is not necessary to do this; you can plant it about 4 inches deeper, but why not enjoy the show. I find it really enjoyable witnessing this touch of Spring.

Once sprouted, young plants require significant amounts of light. My flourescent lights are just inches from the top of the plant. A minimum 2000 lumens is a good choice. A timer is set to keep the lights on 14 hours a day. Frank, my mentor, keeps his on all the time. Regular light bulbs will not do the job. Official grow lights are not required.

Carol’s don’t-do-it-yourself option

Too much trouble? Too iffy? No lights? Forget about potting up your own dahlias. Wait till May. Then go to a garden club or dahlia club plant sale where someone else already started the plants for you. Good for the club and good for early blooms. Details coming soon.