plants that haven't bloomed - Ask Extension
I have a place in my yard where 3 different plants have grown, even thrived, but never bloomed. First was a wisteria, second was a lilac and now, cre...
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plants that haven't bloomed #926234
Asked March 18, 2026, 12:59 PM EDT
I have a place in my yard where 3 different plants have grown, even thrived, but never bloomed. First was a wisteria, second was a lilac and now, crepe myrtles. There is a crepe myrtle near by that blooms nicely. Could it be something in the soil and if so, where can I have the soil tested?
Montgomery County Maryland
Expert Response
It is unlikely to be related to soil nutrient or acidity conditions, though it never hurts to test the soil anyway just to learn what traits it has. The linked page provides information on soil testing and has a short list of regional labs that could be used.
Instead of soil, other conditions are probably responsible for the lack of flowers. All three of those plants are sun-loving, and require a good amount of direct sun (a minimum of 6-8 hours daily in summer) to be vigorous enough to flower well. Does any mature tree or building cast a shadow on that area of the yard, once trees have leafed-out for the season? If so, that would be our prime suspect. Lilacs in particular seem to be notorious for not blooming well if they are not getting full sun.
Our second guess relates to pruning, at least for two plants (wisteria and lilac). Both of them flower on wood (branches or stems) that grew the year prior. If that wood is removed by pruning any time between midsummer or so and the following spring, those flower buds will be lost. Flower buds that are damaged from a cold snap or late freeze/frost after they have begun to break dormancy (such as due to an early spring warm spell) can be damaged or killed, so they won't open and bloom. Crapemyrtle blooms on new wood though, which means it has no dormant flower buds on the branches in winter and only grows them closer to summer. If the crapemyrtle was pruned around June or so, though, that might interrupt flowering.
If anything is exposing these three plants to excess nitrogen (the N in fertilizer N-P-K), which lawn fertilizers often focus on, that can stimulate more leaf growth at the expense of flowers, particularly for legume-family plants like wisteria.
One trick that can work for wisteria vines reluctant to flower is to stress them by root-pruning. This technique uses a shovel to dig a dotted line around a plant (how far from the trunk or main stem depends on how big and old the plant is), without digging anything up, to sever some roots. This minor amount of stress can stimulate flower production the following bloom cycle. We recommend that you remove a wisteria that's one of the invasive species, though, instead of encouraging it to flower and set seed. The invasive species are Japanese (Wisteria floribunda), Chinese (Wisteria sinensis), and their hybrids (Wisteria x formosa).
Miri
Instead of soil, other conditions are probably responsible for the lack of flowers. All three of those plants are sun-loving, and require a good amount of direct sun (a minimum of 6-8 hours daily in summer) to be vigorous enough to flower well. Does any mature tree or building cast a shadow on that area of the yard, once trees have leafed-out for the season? If so, that would be our prime suspect. Lilacs in particular seem to be notorious for not blooming well if they are not getting full sun.
Our second guess relates to pruning, at least for two plants (wisteria and lilac). Both of them flower on wood (branches or stems) that grew the year prior. If that wood is removed by pruning any time between midsummer or so and the following spring, those flower buds will be lost. Flower buds that are damaged from a cold snap or late freeze/frost after they have begun to break dormancy (such as due to an early spring warm spell) can be damaged or killed, so they won't open and bloom. Crapemyrtle blooms on new wood though, which means it has no dormant flower buds on the branches in winter and only grows them closer to summer. If the crapemyrtle was pruned around June or so, though, that might interrupt flowering.
If anything is exposing these three plants to excess nitrogen (the N in fertilizer N-P-K), which lawn fertilizers often focus on, that can stimulate more leaf growth at the expense of flowers, particularly for legume-family plants like wisteria.
One trick that can work for wisteria vines reluctant to flower is to stress them by root-pruning. This technique uses a shovel to dig a dotted line around a plant (how far from the trunk or main stem depends on how big and old the plant is), without digging anything up, to sever some roots. This minor amount of stress can stimulate flower production the following bloom cycle. We recommend that you remove a wisteria that's one of the invasive species, though, instead of encouraging it to flower and set seed. The invasive species are Japanese (Wisteria floribunda), Chinese (Wisteria sinensis), and their hybrids (Wisteria x formosa).
Miri
thank you for your complete and timely response...I appreciate it
On 03/18/2026 5:17 PM EDT Ask Extension wrote:
You're welcome!
