Soil & potting mix
Best soil for Spearmint 'Kentucky Colonel' (Mentha spicata 'Kentucky Colonel')
Also called Kentucky Colonel mint, julep mint.
More about spearmint 'kentucky colonel'
About Spearmint 'Kentucky Colonel'
Mentha spicata 'Kentucky Colonel' · also called Kentucky Colonel mint, julep mint · herb
'Kentucky Colonel' is a large-leaved spearmint prized for mint juleps, with crinkled bright-green foliage and a sweet, intensely fragrant flavor. A vigorous, spreading perennial, it thrives in moist, rich soil and partial to full sun. Grow it in a pot or sunken bottomless container to contain its aggressive runners, and harvest leaves continuously through the growing season.
Preferred mix: Rich, moisture-retentive loam
Watch for — Wilting and crisping: Mint has shallow roots and collapses fast when dry; keep soil evenly moist, especially in containers and heat.
Why spearmint 'kentucky colonel' needs this mix
Spearmint 'Kentucky Colonel' hates drying out, so it wants a mix that stays evenly moist — but it still needs perlite so "moist" never tips into "waterlogged".
- Spearmint 'Kentucky Colonel' comes from damp, shaded forest floors and has fine roots that scorch and brown the moment the rootball dries — the mix has to hold a steady reserve.
- Coir and compost give that reserve, while perlite keeps enough air that the constantly-moist mix does not turn anaerobic.
- Even moisture also keeps its thin leaves from crisping at the edges, which is this plant’s most visible stress signal.
For the full picture on what makes up a good mix, see our guide to the main types of soil and potting media — it explains why each ingredient above behaves the way it does.
What goes wrong with the wrong mix
The wrong soil is one of the most common reasons spearmint 'kentucky colonel' struggles, and the damage often shows up weeks later as a watering problem. For this species specifically:
- A free-draining, gritty mix dries too fast for spearmint 'kentucky colonel' — you get crispy brown edges and frond or leaf drop within days of one missed watering.
- A pure, airless peat mix swings the other way: it holds water but suffocates the fine roots and rots the crown.
- Letting the mix dry to the point it shrinks from the pot is very hard to re-wet evenly and stresses the plant badly.
Using a sharp, fast-draining "houseplant" or cactus-leaning mix that lets spearmint 'kentucky colonel' dry out. It needs a moisture-retentive but still airy blend.
pH — does it matter for spearmint 'kentucky colonel'?
Spearmint 'Kentucky Colonel' prefers a slightly acidic mix (around pH 5.5-6.5); a peat-free compost-and-coir blend sits there naturally, so routine pH testing is unnecessary.
If you want to check or adjust it, the soil pH guide walks through testing and the safe ways to nudge a mix more acidic or more alkaline.
DIY mix vs a bagged one
A good peat-free houseplant compost works for spearmint 'kentucky colonel' straight from the bag if you mix in some perlite for air. The DIY ratio above gives a more reliable moisture-to-air balance.
Drainage and the pot
Use a pot with a drainage hole but a less-porous material (plastic or glazed) so it does not dry too fast. Bottom-watering keeps the mix evenly moist without sogging the crown.
Peat-free mixes slump and compact as they hold moisture, so refresh spearmint 'kentucky colonel''s mix every 12-18 months to keep air in the rootball even if the pot size is unchanged. When the time comes, our repotting guide for spearmint 'kentucky colonel' covers the timing and technique step by step.
Spearmint 'Kentucky Colonel' soil — frequently asked questions
What is the best soil mix for spearmint 'kentucky colonel'?
3 parts peat-free houseplant compost : 1 part coco coir : 1 part perlite. Spearmint 'Kentucky Colonel' comes from damp, shaded forest floors and has fine roots that scorch and brown the moment the rootball dries — the mix has to hold a steady reserve.
Can I use normal potting soil for spearmint 'kentucky colonel'?
A free-draining, gritty mix dries too fast for spearmint 'kentucky colonel' — you get crispy brown edges and frond or leaf drop within days of one missed watering. A good peat-free houseplant compost works for spearmint 'kentucky colonel' straight from the bag if you mix in some perlite for air. The DIY ratio above gives a more reliable moisture-to-air balance.
Does spearmint 'kentucky colonel' need a special pH?
Spearmint 'Kentucky Colonel' prefers a slightly acidic mix (around pH 5.5-6.5); a peat-free compost-and-coir blend sits there naturally, so routine pH testing is unnecessary.
Should I buy a bagged mix or make my own for spearmint 'kentucky colonel'?
A good peat-free houseplant compost works for spearmint 'kentucky colonel' straight from the bag if you mix in some perlite for air. The DIY ratio above gives a more reliable moisture-to-air balance.
How often should I refresh the soil for spearmint 'kentucky colonel'?
Peat-free mixes slump and compact as they hold moisture, so refresh spearmint 'kentucky colonel''s mix every 12-18 months to keep air in the rootball even if the pot size is unchanged. Use a pot with a drainage hole but a less-porous material (plastic or glazed) so it does not dry too fast. Bottom-watering keeps the mix evenly moist without sogging the crown.
Keep reading
- Spearmint 'Kentucky Colonel' care — the full brief (light, water, humidity, problems, pet safety)
- How often to water spearmint 'kentucky colonel' — the schedule the mix feeds into
- Repotting spearmint 'kentucky colonel' — when and how to refresh the mix
- Soil pH guide — test it and adjust it safely
- Underwatered plant — signs and how to rehydrate it
- Why is my plant wilting? Wet vs dry diagnosis
- Should I water my plant? The simple check first
- Best soil for basil
- Best soil for herb garden
- Best soil for mint
- All 2464 soil and potting-mix guides in the Growli library