Lilies: Planting Depth and Distance

How Deep to Plant Lily Bulbs: Depth and Spacing Guide

How deep should you plant a lily bulb? There is no single measurement that works for every lily. The correct planting depth depends on the size of the bulb, how the lily produces roots, the soil, and the particular species or hybrid you are growing.

True lilies in the genus Lilium grow from fleshy, scale-covered bulbs, but they do not all root in exactly the same way. Some produce roots mainly from the base of the bulb. Others also develop roots from the underground portion of the stem and are normally planted more deeply. Small species bulbs need a different approach from large hybrid bulbs, while Lilium candidum, the Madonna lily, is the famous shallow-planted exception.

Spacing matters too. Plant lilies too close together and established clumps can eventually become crowded. Space them too widely and you may lose the bold garden effect that makes lilies so striking. The goal is to give bulbs enough room for roots, stems, offsets, and air circulation while still creating a generous display.

1 Why Lily Planting Depth Varies

The familiar advice to plant bulbs two or three times their height is useful for many flowering bulbs, but lilies deserve a more precise approach. Lily bulbs vary enormously in size and, more importantly, in how their roots develop.

Some lilies are basal-rooting. Their permanent roots develop from the basal plate at the bottom of the bulb. Asiatic lilies are the example specifically used by RHS for this rooting type.

Other lilies are stem-rooting. These produce roots from the base of the bulb and additional seasonal roots from the underground portion of the stem immediately above it. Tiger lily, Lilium lancifolium, and Lilium longiflorum are examples. These lilies need sufficient soil around the buried stem for those additional roots to develop.

Bulb size is another reason fixed measurements can be misleading. A small wild-lily bulb and a large mature hybrid bulb should not automatically receive the same amount of soil cover.

2 Basal-Rooting vs Stem-Rooting Lilies

The distinction between basal-rooting and stem-rooting lilies explains why two healthy lily bulbs may legitimately require different planting depths.

RHS recommends planting basal-rooting lilies, and lilies whose rooting type is unknown, at a depth equal to the height of the bulb. In light sandy soil, they can be planted slightly deeper.

Stem-rooting lilies are planted more deeply, at roughly two-and-a-half times the height of the bulb. This provides the underground stem with the soil volume it needs to develop temporary stem roots during active growth.

The North American Lily Society provides another useful benchmark based on bulb size, recommending about 3-4 in. (7-10 cm) of soil over smaller bulbs and about 4-6 in. (10-15 cm) over larger ones.

These recommendations should not be forced into a single mathematical rule. They come from slightly different systems of describing planting depth. What they agree on is more important: large bulbs and stem-rooting lilies generally need more depth than small bulbs and basal-rooting types, while a few species have their own requirements.

3 How Deep to Plant Asiatic Lilies

Asiatic lilies are among the easiest and most adaptable lilies to grow. RHS specifically uses Asiatic hybrids as an example of lilies that root from the base of the bulb only.

That means there is no need to bury every Asiatic bulb at the old fixed recommendation of 8 in. (20 cm). Instead, follow the basal-rooting guidance and take the size of the bulb into account. Slightly deeper planting is suitable in light sandy soil.

Asiatic lilies can multiply into increasingly substantial clumps, so generous spacing is especially useful in permanent plantings.

4 How Deep to Plant Oriental and Orienpet Lilies

Oriental lilies and Orienpet lilies often produce substantial bulbs and strong flowering stems. Rather than assigning every Oriental or Orienpet cultivar one fixed planting depth, use the size of the bulb and, where known, the rooting habit of the particular lily as your guide.

North American Lily Society guidance provides a useful practical benchmark for larger lily bulbs: about 4-6 in. (10-15 cm) of soil above the bulb. Where a lily is known to produce roots from the underground stem above the bulb, sufficient depth should be allowed for those stem roots to develop.

Good drainage matters more than achieving an exact measurement to the nearest inch. Oriental and Orienpet bulbs should never sit in persistently waterlogged soil. If the site remains wet, improve the drainage, use a raised bed, or grow the lilies in containers rather than simply planting the bulbs more deeply.

5 How Deep to Plant Trumpet Lilies

Trumpet and Aurelian lilies include some of the tallest and most dramatic garden lilies. Mature plants can carry large clusters of fragrant flowers on substantial stems, so both planting depth and spacing deserve attention.

Very tall lilies may eventually need support. If staking will be necessary, positioning the support while you still know exactly where the bulb lies reduces the risk of damaging it later.

6 How Deep to Plant Tiger Lilies

Tiger lilies, most commonly Lilium lancifolium, are useful examples of stem-rooting lilies. They produce roots from the bulb’s base as well as from the underground section of stem above the bulb.

Tiger lilies are vigorous and can multiply through bulbs and bulbils, so a little extra room at planting can reduce overcrowding later.

7 How Deep to Plant Martagon Lilies

Martagon lilies deserve thoughtful planting because they can be slow to settle after planting or transplanting and are best left undisturbed once established.

Rather than forcing every Martagon bulb into one exact measurement, take bulb size and any species- or cultivar-specific instructions into account. A medium or large bulb needs adequate soil cover, but excellent drainage remains essential.

Site choice may matter even more than an extra inch of planting depth. Martagons are among the lilies most comfortable in light or dappled shade and generally perform well in humus-rich, well-drained soil.

8 Madonna Lily Is the Important Exception

The usual lily planting rules change dramatically for Lilium candidum, the Madonna lily.

This historic Mediterranean species should be planted very shallowly. RHS recommends keeping the nose or point of the bulb close to the soil surface, while the North American Lily Society advises no more than about 1 in. (2.5 cm) of settled soil above it. Space the bulbs approximately 8-10 in. (20-25 cm) apart.

This is not simply a small adjustment to the normal lily rule. Burying Madonna lily bulbs at the depth often used for a large Oriental, Trumpet, or stem-rooting lily can impair their performance.

9 Species Lilies Need Species-Specific Depths

Species lilies are far too diverse for one universal planting-depth rule. The group includes tiny and large bulbs, basal-rooting and stem-rooting species, and even lilies with rhizomatous underground growth.

RHS recommends planting small-bulbed Lilium pumilum about 3 in. (8 cm) deep and approximately 4-6 in. (10-15 cm) apart.

At the other end of the spectrum, species such as Lilium formosanum var. pricei, Lilium lancifolium, and Lilium longiflorum can produce stem roots and therefore require the deeper stem-rooting approach.

Rhizomatous lilies are different again. RHS recommends planting Lilium pardalinum and its hybrids about 4 in. (10 cm) deep and 12 in. (30 cm) apart because their underground growth spreads horizontally.

This diversity is why “species lily” is not a planting instruction. If you are growing an unusual wild lily, check that particular species rather than borrowing the depth from an unrelated hybrid.

10 How Far Apart Should Lily Bulbs Be?

Spacing recommendations vary because the ideal distance depends on bulb size, cultivar vigor, garden design, and how long the planting will remain undisturbed.

RHS recommends spacing lily bulbs about 6 in. (15 cm), or roughly three times the diameter of the bulb, apart. This is a useful general starting point, but it is not a command to plant every lily exactly 6 in. from its neighbor. Small species may have their own recommendations, while large, vigorous lilies can benefit from more room.

Closer planting creates an impressive display quickly, while wider spacing gives bulbs more room to multiply before the clump needs attention. Think about what the planting will look like in three or four years, not just on planting day.

Should You Plant Lilies in Groups?

From a design perspective, lilies usually look better when several bulbs of the same cultivar are grouped together rather than scattered individually through a border.

Three bulbs can form an attractive group, while five or more produce a much stronger display where space allows. Position the bulbs informally rather than in a rigid straight line so the resulting stems look integrated with the rest of the planting.

If you are combining several lily cultivars, consider height and flowering time as well as color. Randomly mixing a compact early Asiatic lily with a towering late Orienpet can create a disconnected effect. Repeating individual cultivars in separate groups usually creates a more coherent planting while still allowing different lilies to extend the flowering season.

For ideas on plants that grow well alongside lilies, see Gardenia’s Great Companion Plants for Lilies.

Does Soil Type Change Lily Planting Depth?

Yes, but drainage matters more than being an inch or two away from a theoretical perfect depth.

RHS advises planting basal-rooting lilies slightly deeper in light sandy soil. Sandy ground drains rapidly and generally remains well aerated, so the bulb can tolerate a little more depth.

Heavy clay presents the opposite problem. Lilies do not perform well in poorly drained or waterlogged soil because their bulbs and roots are vulnerable to rot. Simply burying a bulb deeper in compacted clay may place it in an even wetter and less aerated layer.

If your soil remains persistently wet, do not try to solve the problem by adjusting planting depth alone. Improve the root environment, use a raised bed or better-drained planting area, or grow the lilies in containers.

How to Plant Lily Bulbs Step by Step

Once you have determined the appropriate planting depth and spacing, the actual planting process is straightforward.

1. Choose a well-drained site. Most lilies grow well in sun or partial shade, although individual groups have their own preferences.
2. Check the soil. Avoid sites that remain saturated after rain. Improve drainage or use containers if necessary.
3. Prepare a generous planting area. Loosen compacted soil below and around the eventual bulb position so roots can spread easily.
4. Determine the planting depth. Consider bulb size, rooting habit, and any species-specific requirements.
5. Set the bulb the right way up. Position the basal plate and attached roots downward, with the pointed end or scales facing upward.
6. Handle roots carefully. Spread existing roots gently rather than crushing them beneath the bulb.
7. Backfill with soil. Work soil around the bulb without leaving large air pockets.
8. Water after planting. This settles soil around the bulb and roots.
9. Mark the planting site. A discreet label helps prevent accidental digging or damage before shoots emerge.

If you are planting a very tall lily, consider installing its support while you can still see exactly where the bulb is located. Driving a stake blindly into an established lily clump later risks damaging the hidden bulb.

Planting Lily Bulbs in Containers

Lilies perform beautifully in pots, and containers can be especially useful where garden soil is poorly drained or unsuitable for a particular lily. See Gardenia’s Best Lilies for Pots and Containers for cultivar suggestions and detailed container-growing advice.

Choose a container deep enough for proper root development and make sure it has generous drainage holes. RHS recommends leaving about 2 in. (5 cm) between neighboring bulbs and between the bulbs and the edge of the container. As a general guide, three bulbs can be planted in a container about 14 in. (35 cm) wide.

Use the same rooting principles as in open ground: basal-rooting types generally require less depth, while stem-rooting lilies need more room above the bulb. Tall lilies also need sufficiently large, stable containers to prevent the flowering stems from making the pot top-heavy.

Containers can be especially useful for Oriental lilies where garden soil is alkaline, as a suitable acidic growing medium can be provided more easily.

Common Lily Planting Mistakes

• Using one fixed depth for every lily: Bulb size, rooting habit, and species all matter.
• Misreading a planting-depth measurement: Check whether a source is describing planting depth relative to bulb height or specifying soil cover above the bulb.
• Planting Madonna lilies too deeply: Lilium candidum is the major shallow-planted exception.
• Treating tiny species bulbs like large hybrids: Small bulbs usually require less depth.
• Ignoring stem roots: Known stem-rooting lilies need sufficient buried stem for those additional roots to develop.
• Confusing soil preparation with bulb depth: Preparing a bed deeply does not mean planting the bulb at the bottom of it.
• Burying bulbs deeply in waterlogged soil: Good drainage remains essential regardless of planting depth.
• Crowding a permanent planting: Lilies can increase over time, so allow room for future growth.
• Ignoring unusual species: Rhizomatous lilies and other specialty species may have very different requirements.
• Leaving bulbs unplanted for too long: Lily bulbs lack the dry protective tunic found on tulips and daffodils and should be planted promptly so they do not dry out.

Can Planting Depth Affect Lily Flowering?

Correct planting depth helps lilies develop healthy roots, remain anchored in the soil, and, in stem-rooting types, produce the additional roots that support vigorous seasonal growth. But planting depth is only one part of successful flowering.

A correctly planted lily can still fail to bloom if the bulb is immature or weakened, the site is too shady, the soil remains waterlogged, drought interrupts growth, frost damages the emerging stem, pests or disease reduce vigor, or green foliage was removed too early after flowering the previous year.

Healthy leaves but no flowers? See Gardenia’s Why Are My Lilies Not Blooming? Causes and Solutions guide to diagnose the problem.

For complete information on planting, soil, light, watering, feeding, staking, aftercare, winter care, pests, and other growing requirements, see Gardenia’s How to Grow Lilies: Complete Planting and Care Guide.

Frequently Asked Questions

The Bottom Line: How Deep and How Far Apart to Plant Lilies

There is no single planting depth that is correct for every lily. Start with the bulb itself. Consider its size and, where known, whether it is basal-rooting or stem-rooting. Basal-rooting lilies are generally planted less deeply, while stem-rooting lilies need sufficient buried stem for their additional roots to develop.

Then check for exceptions. Lilium candidum belongs close to the soil surface. Small species such as Lilium pumilum are planted relatively shallowly, while rhizomatous species such as Lilium pardalinum need enough horizontal space to spread.

Spacing should reflect the future planting, not just the bulb in your hand. About 6 in. (15 cm), or roughly three times the bulb diameter, is a useful general starting point, but vigorous lilies and permanent clumps can benefit from more room. Bulbs in containers, by contrast, can be grouped much more closely for an immediate display.

Most importantly, do not let an obsession with the exact inch obscure the fundamentals. Choose healthy bulbs, understand what you are planting, provide excellent drainage, give vigorous lilies enough room, and pay attention to the few species that break the general rules. Those decisions matter more than forcing every lily into one universal planting formula.

References

• Royal Horticultural Society: How to Grow Lilies – basal-rooting and stem-rooting lilies, planting depth, spacing, small species, Madonna lily, rhizomatous lilies, soil, and staking.
• Royal Horticultural Society: Lilies in Containers – container size, drainage, bulb spacing, and growing media.
• North American Lily Society: Planting Lilies – soil preparation, drainage, bulb depth, Madonna lily, spacing, and planting technique.
• North American Lily Society: Types of Lilies – lily divisions, species, hybrids, and group characteristics.

Updated: August 2026 • Reviewed by Gardenia Editors