Struggling to Know When to Prune? Monty Don’s Rhyme Makes It Easy (So Long As You Use It Correctly)

Knowing when to prune is one of the most confusing parts of gardening. Prune too early and you risk cutting away flowers; prune too late and you may stress the plant or limit growth. It’s no wonder so many gardeners hesitate, secateurs in hand, unsure whether to act or wait. If only there were a rule (or a rhyme, even!) to help us get it right, eh?

Now, Monty Don is one of those gardeners whose reputation precedes them, whatever country he's in. It makes sense that his pruning rule (which, yes, absolutely does rhyme) has become almost as popular as the Three Ds one: “If it flowers before June, do not prune.”

Now, for many gardeners, this single sentence has prevented years of accidental flower loss. For American gardens scattered across different USDA zones, however, it needs a little translation to work properly.

Monty Don's Pruning Rhyme

The appeal of Monty Don’s rhyme lies in its simplicity. Think about it; rather than forcing us to memorize dozens of plant-specific pruning instructions, it gives gardeners a clear pause point. If a shrub blooms in spring, the message is simple: step the heck away from the pruners.

Obviously it also helps that behind the rhyme is a solid horticultural principle. Most spring-flowering shrubs form their buds on old wood – growth made the previous year – and pruning before they bloom removes those buds, which means no flowers that season.

Waiting until after flowering, then, allows you to shape the plant without sacrificing next year’s display.

So far, so good – but there's no getting away from the fact that American gardeners can run into trouble with... well, with the calendar itself. After all, Monty Don gardens in the UK, where seasonal timing is relatively consistent. In the US, planting zones range from USDA Zones 3 to Zone 10, and spring arrives weeks – sometimes months – apart depending on location.

Still, while June in Maine looks very different from June in Texas, that doesn’t make the rule wrong. it does, however, mean it shouldn’t be followed by the month alone. Instead of focusing on the date, US gardeners should focus on when a plant flowers.

The US-Friendly Version of Monty Don’s Rhyme

To make this advice work across American climates, we just need to tweak Monty Don's rhyme a little. And, luckily for y'all, this writer studied Poetry as one of her Creative Writing modules when she was at university many eons ago.

So, here we go:

If it flowers in spring, prune after flowering.

If summer’s when the flowers appear, prune in winter (or early in the year).

This keeps the spirit of Monty Don’s rule intact while adapting it to local conditions. Observing your garden – rather than the calendar – becomes the most reliable guide.

Pruning Essentials:

To help hammer this one home, here's how the rule applies to familiar shrubs found across US gardens:

Lilac, azalea, forsythia, mock orange

These bloom in spring on old wood. Prune them after flowering finishes.

Bigleaf hydrangea (Hydrangea macrophylla)

Many varieties flower on old wood, though some newer types bloom on both old and new wood. Prune only after blooming, and keep cuts light.

Panicle and smooth hydrangeas

These bloom on new wood and can be pruned in late winter or early spring.

Summer-flowering shrubs (like butterfly bush)

These benefit from early-season pruning before new growth begins.

Roses can be more complex, but many modern shrub and hybrid tea roses are pruned in early spring, just as buds begin to swell – offering us yet another example of watching the plant rather than the date.

One of the biggest takeaways from Monty Don’s advice is confidence in doing nothing. Many shrubs don’t need annual pruning at all, and over-pruning can actually lead to excessive leafy growth, fewer flowers, and stressed plants.

So, if your shrub is healthy, flowering well, and holding its shape, it’s often best left alone. Or, y'know, if it flowers with flair and stays in its lane, back away slowly and don’t cause it pain.

Rhyming games aside, remember that Monty's advice works because it encourages patience and observation, both of which are skills every good gardener develops over time. Remember, nature doesn’t follow a fixed calendar; plants respond to temperature, daylight, and local conditions, not dates on the page (which is why our tomatoes stay so green sometimes, and our bulbs bloom earlier than expected).

Just let your plants show you what they need. The rest should come easily enough.