Californian poppies not growing? Joe Lamp'l warns against these common poppy-growing mistakes

Growing Californian poppies is often described as effortless – so much so that, in some areas, these easy-going, self-seeding flowers are considered invasive. However, as gardener and presenter Joe Lamp'l points out, even this low-maintenance flower can suffer from incorrect care. 

Poppies famously thrive in poor soil – we explain this in our guide on how to grow poppies – and the Californian variety is very drought-tolerant, meaning that in areas with warm summers, these poppies require very little maintenance. So, why are my Californian poppies not blooming, you might be asking? What could possibly have gone wrong? You likely are making one of these top mistakes, according to Joe.  

1. You've transplanted them

As Joe explains in an article in the Seattle Times, Californian poppies 'don’t tolerate transplanting', and that has to do with the fact that they're a wildflower annual not a perennial poppy. 

What these plants need is to be planted where they are to flower – and later scatter their seed to flower again next year in the same spot. If you are raising your Californian poppies indoors and then hardening them off as though they were any other tender annual, you won't have success with these flowers. If you live in a zone colder than 5, just sow them later, after the spring frosts have passed. 

If you're sowing your poppies as part of a bigger meadow scheme, consult our guide on how to plant a wildflower meadow in your garden.

2. You're not raising them correctly from seed

Another thing with California poppies is that the method for sowing them is a little different from many other meadow flowers. Joe writes: 'Sow their seeds by placing, not scattering, two or three seeds in holes the recommended distance apart.' If you simply scatter your Californian poppy seeds, they probably won't germinate at all. 

Once you have seedlings, don't forget to thin them out, 'leaving only the healthiest one.'

3. You're not mulching

But Californian poppies are an option for the best drought tolerant plants, right? Yes, but they don't like to have their roots baked. In fact, in areas with really dry, hot summers, Californian poppies stop blooming by summer for this reason. Joe's tip is: 'Heat-loving flowers will do even better if they’re mulched. Mulch keeps plant roots cool and lets rain and irrigation water soak slowly into the soil rather than running off. Mulch also slows evaporation.' If your poppies aren't blooming throughout the summer, mulching may improve the situation. 

Find out more on mulching in our guide – all plants in your garden will benefit.