You have a lovely new lavender plant and you really want this one to last 15 years.
Here are some tips we use to help our plants last and stay healthy:
Plant your new plant in the spring (After the last frost and no later than mid June) or in the fall (mid August thru September in the Maryland area). We have better results with our fall plantings.
Allow nursery plants to harden off first. Keep them in a semi-shaded area to develop a natural coating which will protect them from the outside elements (1-2 weeks).
Choose a spot with full sun and away from moist, wet areas to avoid root rot.
Mix equal parts bone meal, compost/organic material and lime. Put 1/4 cup of the mixture in the bottom of the whole dug for your plant to fertilize and create an ideal PH level (6.7-7.3).
Do not mulch with wood chips which may lead to fungus growth (not good for lavender). Choose harder mulching material such as oyster shells or pebbles or smooth stones.
Keep larger plants moist for a few weeks until it is established. Then let nature water it with the rain. Seedlings should not be allowed to dry out for more than 1-2 days. Allow them to dry out & then add water to moisten so their tiny roots do not dry out.
If there is a long dry spell with no rain and high temperatures for 2+ weeks, give established plants a watering to avoid heat shock. Being too hot and too dry for too long will burn the plant and it's roots, causing it to die (Been there; done that).
Trim any buds off the first year. This will encourage the plants energy to focus in the root system, giving it a good foundation.
Trim in the fall and/or spring (See future blog post for Tips on Trimming).