The One Gardening Task to Delay Until After the Heatwave – to Guarantee a Vibrant and Abundant Yard
Adding new plants to the yard in extreme temperatures doesn't always end well
As a record-breaking heatwave scorches its way across eastern parts of the US, it's important to proceed carefully with your gardening to-do list. In particular, there's one gardening job to never do in a heatwave: planting out new plants and seedlings.
Although it's still May and the ground is very workable to add new plants to the yard, doing so during temperature spikes can cause heat stress and actually result in plants declining quickly. Instead, it's best to keep them hydrated in a cooler spot and wait for the short-term hot temps to lower again before planting.
So, alongside knowing how to water plants during a heatwave, it's important to understand why exactly you should delay any planting you haven't yet done. And don't worry, there'll be another opportunity to do so before summer arrives.
Why You Shouldn't Plant in a Heatwave
You may have some plants waiting to be added to the garden as part of your spring gardening checklist, but with the current skyrocketing high temperatures it's best to wait.
'Plants, especially seedlings, are highly vulnerable to temperature spikes.
Seedlings have small roots which are especially susceptible to the top few inches of soil drying out when the temperatures soar in a heatwave,' says Drew Swainston, Gardens Content Editor at Homes & Gardens.
'They need to be consistently moist, which is easier said than done in such conditions,' he explains.
With soil drying out much more quickly in higher temps, newly introduced plants are much more vulnerable to failing to establish. It can result in dehydration and symptoms like drooping, wilting, and even death.
'The strong rays also put seedlings at increased risk of transplant shock. When the temperatures are that high, it will lose a lot of water through the leaves and struggle to replace it. The result can be wilting or dying in extreme circumstances,' Drew says.
This isn't to say it's impossible to plant out your seedlings and young plants during this time, but it does require lots of attention and maintenance.
'You can puddle in seedlings – where you fill the planting hole with water before putting the seedlings in – to really give it immediate moisture,' Drew notes.
'However, even then, you need to be very vigilant about watering to ensure the soil doesn’t dry out. A seedling can quickly wilt and die in a heatwave, so always water deeply and do it ideally early in the morning,' Drew advises.
You should use a soil moisture meter (like this one from Amazon) during extreme weather to monitor how quickly the soil is drying out before watering plants in hot weather.
Another thing you can do to help protect seedlings and young plants already in the ground is mulching. This can lock in moisture and regulate soil temperature to prevent shock. This organic mulch from Lowe's is a good option.
'It can be advisable to cover them with shade cloth (like this from Amazon) if you do plant them during these hot spells, to give them respite from the strong sunlight,' Drew adds.
Nevertheless, heatwave tend to last only for a few days to weeks at a time before subsiding. So, there is likely to be another window for planting in milder temperatures before the summer season settles in.
Drew has worked as a writer since 2008 and was also a professional gardener for many years. As a trained horticulturist, he worked in prestigious historic gardens, including Hanbury Hall and the world-famous Hidcote Manor Garden. He also spent time as a specialist kitchen gardener at Soho Farmhouse and Netherby Hall, where he grew vegetables, fruit, herbs, and cut flowers for restaurants. Drew has written for numerous print and online publications and is an allotment holder and garden blogger. He was shortlisted for the Digital Gardening Writer of the Year at the 2025 Garden Media Guild Awards.
What to Shop
This soil moisture meter can help you avoid watering mistakes. Simply insert the probe and it will identify how wet the soil is.
This premium organic mulch can be used to protect plants in extreme heat, locking in moisture and regulating soil temperature.
Use this drip irrigation kit to install a controlled watering system in your yard. It includes 1/2 and 1/4 inch irrigation tubing.
FAQs
Can You Sow Seeds During a Heatwave?
While you can sow seeds outdoors during a heatwave, it is very challenging. Seed germination requires consistent moisture, which is hard to maintain during high temperatures. At the same time, seeds can actually dehydrate and burn during a heatwave, reducing their viability and likelihood of germinating. For this reason, you may wish to delay your seed sowing until the weather conditions are milder again.
One way to boost your yard's resilience during extreme weather like a heatwave is by putting in an irrigation system. The Garden in Minutes Garden Grid is a great option, with multiple sizes available for a bespoke fit in your yard.
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